Borated ethylene alpha-olefin copolymer substituted Mannich base lubricant dispersant additives

ABSTRACT

The present invention is directed to oil-soluble lubricating oil additives comprising borated Mannich Base condensates of an alkyl substituted hydroxy aromatic compound with formaldehyde and an amine, wherein the alkyl-moiety of the aromatic compounds is derived from at least one ethylene alpha-olefin copolymer of 300 to 20,000 number average molecular weight, wherein at least about 30% of the polymer&#39;s chains contain terminal ethenylidene unsaturation. The borated Mannich Base condensates of this invention are useful as dispersants.

This is a division of application Ser. No. 959,021, filed Oct. 9, 1992is a Rule 60 Continuation of U.S. patent application Ser. No. 788,907filed Nov. 7, 1991 now abandoned which is a Rule 60 Divisional of U.S.patent Ser. No. 473,625 filed Feb. 1, 1990, U.S. Pat. No. 5,209,103which is a continuation-in-part of U.S. patent application Ser. No.226,604 filed Aug. 1, 1988, U.S. Pat. No. 5,017,299.

FIELD OF THE INVENTION

This invention relates to improved oil soluble dispersant additivesuseful oleaginous compositions, including fuel and lubricating oilcompositions, and to concentrates containing said additives.

BACKGROUND OF THE INVENTION

U.S. Pat. No. 3,442,808 relates to lubricating oil additives prepared byreacting alkenyl succinic anhydride with the Mannich condensationproduct prepared by condensing alkyl substituted phenol, formaldehydeand polyalkylene polyamine.

U.S. Pat. 3,458,495 relates to oxidation inhibitors anddispersant-detergent oil additives comprising the reaction product ofone equivalent of a phosphosulfurized hydrocarbon and about 0.5 to 4equivalents of an alkylene amino phenol . The phosphosulfurizedhydrocarbons are prepared by reacting a terpene, a petroleum fraction ora 500 to 200,000 molecular weight C₂ to C₆ olefin polymer (includingpolymers of ethylene, propylene, butylene, isobutylene or isoamylene)and from 5 to 40wt. % of a sulfide of phosphorous. The alkylene aminophenol is prepared by a Mannich Base condensation of aldehyde, alkylenepolyamine and alkyl phenol.

U.S. Pat. 4,354,950 discloses a method of preparing Mannich basederivatives of hydroxyaryl succinimides of the formula: ##STR1## whereinR is hydrocarbyl of 25 to 200 carbon atoms, R' is H, alkyl or halogen,"n" is 2 or 3 , "m" has a value of 1 to 5, Y is H or a methylenehydroxyaryl succinimide radical, "x" has a value of 1 to 2 when Y is Hand a value of 1 when Y is a methylene hydroxyaryl succinimide radical.The above succinimides are formed in a stepwise reaction, e.g., byreacting a polyalkenyl succinic anhydride with an aminophenol, toproduce an intermediate N- (hydroxyaryl) hydrocarbyl succinimide, whichis then reacted with an alkylene diamine and an aldehyde (e.g.,formaldehyde) in a Mannich base reaction to produce the describedsuccinimides. The described succinimides may be added to a base oil oflubricating viscosity to form lubricant concentrates and lubricating oilformulations.

U.S. Pat. No. 4,668,834 to Uniroyal Chemical discloses preparation andcomposition of ethylene-alpha olefin copolymers and terpolymers, whichare disclosed to be useful as intermediates in epoxy-graftedencapsulation compositions.

Japanese Published Patent Application 87-129,303A of MitsuiPetrochemical relates to narrow molecular weight distribution (M_(w)/M_(n) <2.5 ) ethylene alpha-olefin copolymers containing 85-99 mol %ethylene, which are disclosed to be used for dispersing agents,modifiers or materials to produce toners. The copolymers (havingcrystallinity of from 5-85%) are prepared in the presence of a catalystsystem comprising Zr compounds having at least one cycloalkadienyl groupand alumoxane.

European Patent 128,046 discloses (co)polyolefin reactor blends ofpolyethylene and ethylene higher alpha-olefin copolymers prepared byemploying described dual-metallocene/alumoxane catalyst systems.

European Patent Publication 129,368 discloses metallocene/alumoxanecatalysts useful for the preparation of ethylene homopolymer andethylene higher alpha-olefin copolymers.

European Patent Application Publication 257,696 Al relates to a processfor dimerizing alpha-olefins using a catalyst comprising certainmetallocene/alumoxane systems.

PCT Published Patent Application WO 88/01626 relates to transition metalcompound/alumoxane catalysts for polymerizing alpha-olefins.

M. B. Bogdanov et al., "Oxidative Thermal Degradation of AlkenylSuccinic Anhydrides", Neftehimiya 13:743-748 (1973) (Englishtranslation) relates to a study of the thermal oxidative stability ofthe reaction products of succinic anhydride with polyisobutylene orethylene-propylene copolymer. The study concludes with the most stablereaction product which was the reaction product of succinic anhydrideand ethylene-propylene copolymer containing terminal succinic anhydridegroups and having the lowest content of double bonds in the polymerchain.

SUMMARY OF THE INVENTION

In accordance with one aspect of the present invention, there areprovided novel alkylated hydroxy aromatic compounds wherein thealkyl-moiety of the alkyl phenol is derived from at least one terminallyunsaturated ethylene alpha-olefin polymer of 300 to 20,000 numberaverage molecular weight, wherein the terminal unsaturation comprisesethenylidene unsaturation. These compounds are formed in surprisinglyhigh conversions based on the starting ethylene alpha-olefin polymer,providing product mixtures in which unreacted ethylene alpha-olefinpolymer concentrations are minimized, thereby obtaining processingefficiencies. The alkylated hydroxy aromatic compounds so formed areuseful in the preparation of novel Mannich Base dispersants.

In accordance with other aspects of the present invention, anoil-soluble lubricating oil additive is provided which comprises aMannich Base condensate of an alkyl substituted hydroxy aromaticcompound with formaldehyde and an amine, wherein the alkyl-moiety of thearomatic compounds is derived from at least one terminally unsaturatedethylene alpha-olefin copolymer of 300 to 10,000 number averagemolecular weight, wherein the terminal unsaturation comprisesethenylidene unsaturation.

The process of this invention permits the preparation of noveloil-soluble Mannich Base condensate lubricating oil additives which aresimultaneously characterized by a low concentration of unreacted polymer(usually less than about 40wt. %, e.g., from 5 to 35wt. %) and byadvantageous viscosity properties to permit the additives to be readilyhandled. In addition, the novel ethylene alpha-olefin polymerssubstituted Mannich Base condensate additives of this invention can becharacterized by VR values (as hereinafter defined) of not greater thanabout 4.1, thereby providing advantageous viscosity modifying propertiesto the lubricating oils containing them. The present invention canproduce such substituted polymers in a highly concentrated form assubstantially halogen free materials, thereby reducing the corrositivityprocessing difficulties and environmental concerns which are associatedwith halogen-containing lubricating oil additives.

Further, dispersant materials can be prepared from the substitutedpolymers of this invention to provide lubricating oil dispersantproducts having VR' values of not greater than about 4.1 and VR'/VR_(r)ratios of less than about 1.11 (as such values and ratios arehereinafter defined). Surprisingly, the process of this inventionpermits the preparation of highly concentrated, substantiallyhalogen-free dispersants from high molecular weightethylene-alpha-olefin polymers (M_(n) >5000, e.g., 5,500-10,000) ofsuperior viscosity properties.

The materials of the invention are different from the prior art MannichBase materials because of their effectiveness and their ability toprovide enhanced lubricating oil dispersancy, as exhibited by theirenhanced sludge and varnish control properties.

DETAILED DESCRIPTION OF THE INVENTION Preparation of EthyleneAlpha-Olefin Copolymer

The polymers employed in this invention are polymers of ethylene and atleast one alpha-olefin having the formula H₂ C═CHR¹ wherein R¹ isstraight chain or branched chain alkyl radical comprising 1 to 18 carbonatoms and wherein the polymer contains a high degree of terminalethenylidene unsaturation. Preferably R¹ in the above formula is alkylof from 1 to 8 carbon atoms, and more preferably is alkyl of from 1 to 2carbon atoms. Therefore, useful comonomers with ethylene in thisinvention include propylene, 1-butene, hexene-1, octene-1,4-methylpentene-1, decene-1, dodecene-1, tridecene-1, tetradecene-1,pentadecene-1, hexadecene-1, heptadecene-1, octadecene-1, nonadecene-1and mixtures thereof (e.g., mixtures of propylene and 1-butene, and thelike).

Exemplary of such polymers are ethylene-propylene copolymers,ethylene-butene-1 copolymers and the like. Preferred polymers arecopolymers of ethylene and propylene and ethylene and butene-1.

The molar ethylene content of the polymers employed in this invention ispreferably in the range of between about 20 and about 80 percent, andmore preferably between about 30 and about 70 percent. When propyleneand/or butene-1 are employed as comonomer(s) with ethylene, the ethylenecontent of such copolymers is most preferably between about 45 and about65 percent, although higher or lower ethylene contents may be present.

The polymers employed in this invention generally possess a numberaverage molecular weight of from about 300 to about 20,000 (e.g., fromabout 300 to 10,000), preferably from about 900 to 20,500, morepreferably of from about 900 to 10,000 (e.g., from about 700 to about15,000; most preferably of from about 1500 to about 5,000. The numberaverage molecular weight for such polymers can be determined by severalknown techniques. A convenient method for such determination is by sizeexclusion chromatography (also known as gel permeation chromatography(GPC)) which additionally provides molecular weight distributioninformation, see W. W. Yau, J. J. Kirkland and D. D. Bly, "Modern SizeExclusion Liquid Chromatography", John Wiley and Sons, New York, 1979.

Consequently, such polymers generally possess an intrinsic viscosity (asmeasured in tetralin at 135° C.) of between about 0.025 and about 0.9dl/g, preferably of between about 0.05 and about 0.5 dl/g, mostpreferably of between about 0.075 and about 0.4 dl/g.

The polymers employed in this invention preferably exhibit a degree ofcrystallinity such that, when grafted, they are essentially amorphous.

The polymers employed in this invention are further characterized inthat up to about 95% and more of the polymer chains possess terminalethenylidene-type unsaturation. Thus, one end of such polymers will beof the formula POLY--C(T¹)═CH₂ wherein T¹ is C₁ to C₁₈ alkyl ,preferably C₁ to C₈ alkyl , and more preferably C₁ to C₂ alkyl, (e.g. ,methyl or ethyl) and wherein POLY represents the polymer chain. Thechain length of the T¹ alkyl group will vary depending on thecomonomer(s) selected for use in the polymerization. A minor amount ofthe polymer chains can contain terminal ethenyl unsaturation, i.e.POLY--CH═CH₂, and a portion of the polymers can contain internalmonounsaturation, e.g. POLY--CH═CH(T¹), wherein T¹ is as defined above.

The polymer employed in this invention comprises polymer chains, atleast about 30 percent of which possess terminal ethenylideneunsaturation. Preferably at least about 50 percent, more preferably atleast about 60 percent, and most preferably at least about 75 percent(e.g. 75-98%) , of such polymer chains exhibit terminal ethyenylideneunsaturation. The percentage of polymer chains exhibiting terminalethyenylidene unsaturation may be determined by FTIR spectroscopicanalysis, titration, or C¹³ NMR.

The polymer and the composition employed in this invention may beprepared as described in U.S. Pat. No. 4,668,834, in European PatentPublications 128,046 and 129,368, and in co-pending Ser. No. 728,111,filed Apr. 29, 1985, and copending Ser. No. 93,460, filed Sep. 10, 1987,the disclosures of all of which are hereby incorporated by reference intheir entirety.

The polymers for use in the present invention can be prepared bypolymerizing monomer mixtures comprising ethylene in combination withother monomers such as alpha-olefins having from 3 to 20 carbon atoms(and preferably from 3-4 carbon atoms, i.e., propylene, butene-1, andmixtures thereof) in the presence of a catalyst system comprising atleast one metallocene (e.g., a cyclopentadienyl-transition metalcompound) and an alumoxane compound. The comonomer content can becontrolled through the selection of the metallocene catalyst componentand by controlling the partial pressure of the various monomers.

The catalysts employed in the production of the reactant polymers areorganometallic coordination compounds which are cyclopentadienylderivatives of a Group 4b metal of the Periodic Table of the Elements(56th Edition of Handbook of Chemistry and Physics, CRC Press [1975 ])and include mono, di and tricyclopentadienyls and their derivatives ofthe transition metals. Particularly desirable are the metallocene of aGroup 4b metal such as titanium, zirconium, and hafnium. The alumoxanesemployed in forming the reaction product with the metallocenes arethemselves the reaction products of an aluminum trialkyl with water.

In general, at least one metallocene compound is employed in theformation of the catalyst. As indicated, supra , metallocene is a metalderivative of a cyclopentadiene. The metallocenes usefully employed inaccordance with this invention contain at least one cyclopentadienering. The metal is selected from the Group 4b preferably titanium,zirconium, and hafnium, and most preferably hafnium and zirconium. Thecyclopentadienyl ring can be unsubstituted or contain one or moresubstituents (e.g., from 1 to 5 substituents ) such as, for example, ahydrocarbyl substituent (e.g., up to 5 C₁ to C₅ hydrocarbylsubstituents) or other substituents, e.g. such as, for example, atrialkyl silyl substituent. The metallocene can contain one, two, orthree cyclopentadienyl rings; however, two rings are preferred.

Useful metallocenes can be represented by the general formulas:

    I. (Cp.sub.m MR.sub.n X.sub.q

wherein Cp is a cyclopentadienyl ring, M is a Group 4b transition metal,R is a hydrocarbyl group or hydrocarboxy group having from 1 to 20carbon atoms, X is a halogen, and m is a whole number from 1 to 3, n isa whole number from 0 to 3, and q is a whole number from 0 to 3.

    II. (C.sub.5 R'.sub.k).sub.g R" .sub.s (C.sub.5 R' .sub.k)MQ 3 -g and

    III. R".sub.s (C.sub.5 R'.sub.k).sub.2 MQ'

wherein (C₅ R'_(k)) is a cyclopentadienyl or substitutedcyclopentadienyl, each R' is the same or different and is hydrogen or ahydrocarbyl radical such as alkyl, alkenyl, aryl, alkylaryl, orarylalkyl radical containing from 1 to 20 carbon atoms, a siliconcontaining hydrocarbyl radical, or hydrocarbyl radicals wherein twocarbon atoms are Joined together to form a C_(4-C) ₆ ring, R" is a C₁-C₄ alkylene radical, a dialkyl germanium or silicon, or a alkylphosphine or amine radical bridging two (C₅ R'_(k)) rings, Q is ahydrocarbyl radical such as aryl, alkyl, alkenyl, alkylaryl, or arylalkyl radical having from 1-20 carbon atoms, hydrocarboxy radical havingfrom 1-20 carbon atoms or halogen and can be the same or different fromeach other, Q' is an alkylidene radical having from 1 to about 20 carbonatoms, s is 0 or 1, g is 0, 1 or 2, s is 0 when g is 0, k is 4 when s is1, and k is 5 when s is 0, and M is as defined above. Exemplaryhydrocarbyl radicals are methyl, ethyl, propyl, butyl, amyl, isoamyl,hexyl, isobutyl, heptyl, octyl, nonyl, decyl, cetyl, 2-ethylhexyl,phenyl and the like. Exemplary silicon containing hydrocarbyl radicalsare trimethylsilyl, triethylsilyl and triphenylsilyl. Exemplary halogenatoms include chlorine, bromine, fluorine and iodine and of thesehalogen atoms, chlorine is preferred. Exemplary hydrocarboxy radicalsare methoxy ethoxy, butoxy, amyloxy and the like. Exemplary of thealkylidene radicals is methylidene, ethylidene and propylidene.

Illustrative, but non-limiting examples of the metallocenes representedby formula I are dialkyl metallocenes such as bis(cyclopentadienyl)titanium dimethyl, bis(cyclopentadienyl)titanium diphenyl,bis(cyclopentadienyl)zirconium dimethyl, bis(cyclopentadienyl)zirconiumdiphenyl, bis(cyclopentadienyl)hafnium dimethyl and diphenyl,bis(cyclopentadienyl)titanium di-neopentyl,bis(cyclopentadienyl)zirconium di-neopentyl,bis(cyclopentadienyl)titanium dibenzyl, bis(cyclopentadienyl)zirconiumdibenzyl, bis(cyclopentadienyl)vanadium dimethyl; the mono alkylmetallocenes such as bis(cyclopentadienyl)titanium methyl chloride,bis(cyclopentadienyl)titanium ethyl chloridebis(cyclopentadlenyl)titanium phenyl chloride,bis(cyclopentadlenyl)zirconium hydrochloride,bis(cyclopentadienyl)zirconium methyl chloride,bis(cyclopentadienyl)zirconium ethyl chloride,bis(cyclopentadienyl)zirconium phenyl chloride,bis(cyclopentadienyl)titanium methyl bromide,bis(cyclopentadienyl)titanium methyl iodide,bis(cyclopentadienyl)titanium ethyl bromide,bis(cyclopentadienyl)titanium ethyl iodide,bis(cyclopentadienyl)titanium phenyl bromide,bis(cyclopentadienyl)titanium phenyl iodide,bis(cyclopentadienyl)zirconium methyl bromide,bis(cyclopentadienyl)zirconium methyl iodide,bis(cyclopentadienyl)zirconium ethyl bromide,bis(cyclopentadienyl)zirconium ethyl iodide,bis(cyclopentadienyl)zirconium phenyl bromide,bis(cyclopentadienyl)zirconium phenyl iodide; the trialkyl metallocenessuch as cyclopentadienyltitanium trimethyl, cyclopentadienyl zirconiumtriphenyl, and cyclopentadienyl zirconium trineopentyl,cyclopentadienylzirconium trimethyl, cyclopentadienylhafnium triphenyl,cyclopentadienylhafnium trineopentyl, and cyclopentadienylhafniumtrimethyl.

Illustrative, but non-limiting examples of II and III metallocenes whichcan be usefully employed are monocyclopentadienyls titanocenes such as,pentamethylcyclopentadienyl titanium trichloride,pentaethylcyclopentadienyl titanium trichloride,bis(pentamethylcyclopentadienyl)titanium diphenyl, the carbenerepresented by the formula bis(cyclopentadienyl)titanium═CH₂ andderivatives of this reagent such as bis(cyclopentadienyl)Ti═CH₂.Al(CH₃)₃(Cp₂ TiCH₂)₂, CP₂ TiCH₂ CH(CH₃)CH₂, Cp2Ti-CH₂ CH₂ CH₂ ; substitutedbis(Cp)Ti(IV) compounds such as bis(indenyl)titanium diphenyl ordichloride, bis(methylcyclopentadienyl)titanium diphenyl or dihalides;dialkyl, trialkyl, tetra-alkyl and penta-alkyl cyclopentadienyl titaniumcompounds such as bis(1,2-dimethylcyclopentadienyl)titanium diphenyl ordichloride, bis(1,2-diethylcyclopentadienyl)titanium diphenyl ordichloride and other dihalide complexes; silicon, phosphine, amine orcarbon bridged cyclopentadiene complexes, such asdimethylsilyldicyclopentadienyl titanium diphenyl or dichloride, methylphosphine dicyclopentadienyl titanium diphenyl or dichloride,methylenedicyclopentadienyl titanium diphenyl or dichloride and othercomplexes described by formulae II and III.

Illustrative but non-limiting examples of the zirconocenes of Formula IIand III which can be usefully employed are, pentamethylcyclopentadienylzirconium trichloride, pentaethylcyclopentadienyl zirconium trichloride,the alkyl substituted cyclopentadienes, such asbis(ethylcyclopentadienyl)zirconium dimethyl,bis(beta-phenylpropylcyclopentadienyl)zirconium dimethyl,bis(methylcyclopentadienyl)zirconium dimethyl,bis(n-butylcyclopentadienyl)zirconium dimethylbis(cyclohexylmethylcyclopentadienyl)zirconium dimethylbis(n-octyl-cyclopentadienyl)zirconium dimethyl, and haloalkyl anddihydride, and dihalide complexes of the above; dialkyl, trialkyl,tetra-alkyl, and penta-alkyl cyclopentadienes, such asbis(pentamethylcyclopentadienyl )zirconium diphenyl,bis(pentamethylcyclopentadienyl) zirconium dimethyl,bis(1,2-dimethylcyclopentadienyl)zirconium dimethyl and mono anddihalide and hydride complexes of the above; silicon, phosphorus, andcarbon bridged cyclopentadiene complexes such asdimethylsilyldicyclopentadienyl zirconium dimethyl, methyl halide ordihalide, and methylene dicyclopentadienyl zirconium dimethyl, methylhalide, or dihalide. Mono, di and tri-silyl substituted cyclopentadienylcompounds such as bis(trimethylsilylcyclopentadienyl)zirconiumdichloride and dimethyl bis(1,3-di-trimethylsilylcyclopentadienyl)zirconium dichloride and dimethyl andbis(1,2,4-tri-trimethylsilylcyclopentadienyl)zirconium dichloride anddimethyl. Carbenes represented by the formulae CP₂ Zr═CH₂ P(C₆ H₅)₂ CH₃,and derivatives of these compounds such as Cp₂ ZrCH₂ CH(CH₃)CH₂.

Mixed cyclopentadienyl metallocene compounds such as cyclopentadienyl(pentamethyl cyclopentadienyl)zirconium dichloride,(1,3-di-trimethylsilylcyclopentadienyl)(pentamethylcyclopentadienyl)zirconium dichloride, and cyclopentadienyl(indenyl)zirconium dichloride can be employed.

Most preferably, the polymers used in this invention are substantiallyfree of ethylene homopolymer.

Bis (cyclopentadienyl)hafnium dichloride, bis(cyclopentadienyl)hafnium;dimethyl, bis(cyclopentadienyl) vanadium dichloride and the like areillustrative of other metallocenes.

Some preferred metallocenes are bis(cyclopentadienyl) zirconium;dimethyl, bis(cyclopentadienyl)zirconium dichloride;bis(cyclopentadienyl)titanium dichloride;bis(methylcyclopentadienyl)zirconium dichloride;bis(methylcyclopentadienyl)titanium dichloride;bis(n-butylcyclopentadienyl)zirconium dichloride;dimethylsilyldicyclopentadienyl zirconium dichloride;bis(trimethylsilycyclopentadienyl)zirconium dichloride; anddimethylsilyldicyclopentadienyl titanium dichloride;bis(indenyl)zirconium dichloride; bis(4,5,6,7-tetrahydroindenyl)zirconium dichloride; the racemic and/or meso isomer of1,2-ethylene-bridged bis(4,5,6,7-tetrahydroindenyl) zirconiumdichloride; the racemic and/or meso isomer of 1,1-dimethylsilyl-bridgedbis(4,5,6,7-tetrahydroindenyl)zirconium dichloride; and the racemicand/or meso isomer of 1,1-dimethylsilyl-bridgedbis(methylcyclopentadienyl) zirconium dichloride.

The alumoxane compounds useful in the polymerization process may becyclic or linear. Cyclic alumoxanes may be represented by the generalformula (R--Al--O)_(n) while linear alumoxanes may be represented by thegeneral formula R(R--Al--O)n'AlR₂. In the general formula R is a C₁ -C₅alkyl group such as, for example, methyl, ethyl, propyl, butyl andpentyl, n is an integer of from 3 to 20, and n' is an integer from 1 toabout 20. Preferably, R is methyl and n and n' are 4-18. Generally, inthe preparation of alumoxanes from, for example, aluminum trimethyl andwater, a mixture of the linear and cyclic compounds is obtained.

The alumoxane can be prepared in various ways. Preferably, they areprepared by contacting water with a solution of aluminum trialkyl, suchas, for examples, aluminum trimethyl, in a suitable organic solvent suchas toluene or an aliphatic hydrocarbon. For example, the aluminum alkylis treated with water in the form of a moist solvent. In an alternativemethod, the aluminum alkyl such as aluminum trimethyl can be desirablycontacted with a hydrated salt such as hydrated copper sulfate orferrous sulfate. Preferably, the alumoxane is prepared in the presenceof a hydrated ferrous sulfate. The method comprises treating a dilutesolution of aluminum trimethyl in, for example, toluene, with ferroussulfate represented by the general formula FeSO₄.7H₂ O. The ratio offerrous sulfate to aluminum trimethyl is desirably about 1 mole offerrous sulfate for 6 to 7 moles of aluminum trimethyl. The reaction isevidenced by the evolution of methane.

The mole ratio of aluminum in the alumoxane to total metal in themetallocenes which can be usefully employed can be in the range of about0.5: 1 to about 1000:1, and desirably about 1:1 to about 100:1.Preferably, the mole ratio will be in the range of 50:1 to about 5:1 andmost preferably 20:1 to 5:1.

The solvents used in the preparation of the catalyst system are inerthydrocarbons, in particular a hydrocarbon that is inert with respect tothe catalyst system. Such solvents are well known and include, forexample, isobutane, butane, pentane, hexane, heptane, octane,cyclohexane, methylcyclohexane, toluene, xylene and the like.

Polymerization is generally conducted at temperatures ranging betweenabout 20° and about 300° C., preferably between about 30° and about 200° C. Reaction time is not critical and may vary from several hours ormore to several minutes or less, depending upon factors such as reactiontemperature, the monomers to be copolymerized, and the like. One ofordinary skill in the art may readily obtain the optimum reaction timefor a given set of reaction parameters by routine experimentation.

The catalyst systems described herein are suitable for thepolymerization of olefins in solution over a wide range of pressures.Preferably, the polymerization will be completed at a pressure of fromabout 10 to about 3,000 bar, and generally at a pressure within therange from about 40 bar to about 2,000 bar, and most preferably, thepolymerization will be completed at a pressure within the range fromabout 50 bar to about 1,500 bar.

After polymerization and, optionally, deactivation of the catalyst(e.g., by conventional techniques such as contacting the polymerizationreaction medium with water or an alcohol, such as methanol, propanol,isopropanol, etc., or cooling or flashing the medium to terminate thepolymerization reaction), the product polymer can be recovered byprocesses well known in the art. Any excess reactants may be flashed offfrom the polymer.

The polymerization may be conducted employing liquid monomer, such asliquid propylene, or mixtures of liquid monomers (such as mixtures ofliquid propylene and 1-butene), as the reaction medium. Alternatively,polymerization may .be accomplished in the presence of a hydrocarboninert to the polymerization such as butane, pentane, isopentane, hexane,isooctane, decane, toluene, xylene, and the like.

In those situations wherein the molecular weight of the polymer productthat would be produced at a given set of operating conditions is higherthan desired, any of the techniques known in the prior art for controlof molecular weight, such as the use of hydrogen and/or polymerizationtemperature control, may be used in the process of this invention. If sodesired, the polymerization may be carried out in the presence ofhydrogen to lower the polymer molecular weight. Care should be taken toassure that terminal ethenylidene unsaturation is not reduced to lessthan about 30 percent of the polymer chains.

However, the polymers are preferably formed in the substantial absenceof added H₂ gas, that is, the absence of H₂ gas added in amountseffective to substantially reduce the polymer molecular weight. Morepreferably, the polymerizations will be conducted employing less than 5wppm, and more preferably less than 1 wppm, of added H₂ gas, based onthe moles of the ethylene monomer charged to the polymerization zone.

When carrying out the polymerization in a batch-type fashion, thereaction diluent (if any), ethylene and alpha-olefin comonomer(s) arecharged at appropriate ratios to a suitable reactor. Care must be takenthat all ingredients are dry, with the reactants typically being passedthrough molecular sieves or other drying means prior to theirintroduction into the reactor. Subsequently, either the catalyst andthen the cocatalyst, or first the cocatalyst and then the catalyst areintroduced while agitating the reaction mixture, thereby causingpolymerization to commence. Alternatively, the catalyst and cocatalystmay be premixed in a solvent and then charged to the reactor. As polymeris being formed, additional monomers may be added to the reactor. Uponcompletion of the reaction, unreacted monomer and solvent are eitherflashed or distilled off, if necessary by vacuum, and the low molecularweight copolymer withdrawn from the reactor.

The polymerization may be conducted in a continuous manner bysimultaneously feeding the reaction diluent (if employed), monomers,catalyst and cocatalyst to a reactor and withdrawing solvent, unreactedmonomer and polymer from the reactor so as to allow a residence time ofingredients long enough for forming polymer of the desired molecularweight and separating the polymer from the reaction mixture.

Hydroxyaromatic Compounds

The hydroxy aromatic compounds useful in the preparation of thealkylated materials of this invention include those compounds having theformula (IIIa):

    H--Ar--(OH).sub.c

wherein Ar represents ##STR2## wherein a is 1 or 2, R' is a halogenradical such as the bromide or chloride radical, b is an integer from 0to 2, and c in an integer from 1 to 2.

Illustrative of such Ar groups are phenylene, biphenylene, naphthyleneand the like.

Preparation of the Alkylated Hydroxyaromatic Compounds

The selected ethylene alpha-olefin polymer and hydroxy aromatic compoundare contacted in the presence of a catalytically effective amount of atleast one acidic alkylation catalyst under conditions effective toalkylate the aromatic group of the hydroxy aromatic compound. Thealkylation catalyst is conventional and can comprise inorganic acidssuch as H₃ PO₄ H₂ SO₄ HF, BF₃ HF-BF₃ and the like. The acid catalyst canalso comprise an acidic ion exchange resin having acidic groups adsorbedor absorbed thereon, such as Amberlyst 15 resin (Rohm & Haas Co.), andthe like. Also useful as catalysts are preformed complexes (or complexesformed in situ) of the foregoing with C₂ to C₁₀ ethers, C₁ to C₁₀alcohols, C₂ to C₁₀ ketones, phenols and the like, such as BF₃ complexedwith dimethyl ether, diethyl ether, phenol, and the like.

The hydroxy aromatic compound and polymer will be generally contacted ina ratio of from about 0.1 to 10, preferably from about 1 to 7, morepreferably from about 2 to 5, moles of the aromatic compound per mole ofthe polymer. The selected acid catalyst can be employed in widelyvarying concentrations. Generally, when the acid catalyst comprises aninorganic catalyst, the acid catalyst will be charged to provide atleast about 0.001, preferably from about 0.01 to 0.5, more preferablyfrom about 0.1 to 0.3, moles of catalyst per mole of hydroxy aromaticcompound charged to the alkylation reaction zone. Use of greater than Imole of the inorganic catalyst per mole of hydroxy aromatic compound isnot generally required. When the acid catalyst comprises a supportedcatalyst, such as an acidic ion exchange resin, the reactants can becontacted with the ion exchange resin employing any conventionalsolid-liquid contacting techniques, such as by passing the reactantsthrough the resin (e.g., in a catalyst bed or through a membraneimpregnated or otherwise containing the resin catalyst) and the upperlimit on the moles of catalyst employed per mole of hydroxy aromaticcompound is not critical.

The temperature for alkylation can also vary widely, and will usuallyrange from about 20° to 250° C. preferably from about 30° to 150° C.,more preferably from about 50° to 80° C.

The alkylation reaction time can vary and will generally be from about 1to 5 hours, although longer or shorter times can also be employed. Thealkylation process can be practiced in a batchwise, continuous orsemicontinuous manner. Preferably, the acid catalyst is neutralizedand/or removed prior to contacting the alkylation product mixture withthe nucleophilic reagent (e.g., polyamine) and aldehyde reactant. Theneutralization can be accomplished by contacting the crude alkylationproduct with gaseous ammonia or other basically reacting compound (e.g.,aqueous NaOH, KOH, and the like), followed by filtration to remove anyprecipitated neutralized catalyst solids.

Alkylation processes of the above types are known and are described, forexample, in U.S. Pat. Nos. 3,539,633 and 3,649,229, the disclosures ofwhich are hereby incorporated by reference.

The % conversion obtained in the alkylation according to the presentinvention is unexpectedly high and conversions of up to 98% and more canbe achieved. Generally, the conversions will be at least about 70%,e.g., from 70 to 98%, and preferably from 80 to 95%, based on thepercentage of the ethylene alpha-olefin polymer charged which reacts.The precise conversion obtained will depend on the M_(n) of the polymer,the alkylation temperature, reaction time and other factors, andconversions will generally decrease somewhat as polymer M_(n) increases.The alkylation process of this invention is particularly beneficial forpolymers having M_(n) of from about 300 to 5,000, preferably 300 to3,000.

It will be understood that the ethylene alpha-olefin polymers of thisinvention which are charged to the alkylation reaction zone can becharged alone or together with (e.g., in admixture with) otherpolyalkenes polyalkenes derived alkenes having from 1 to 20 carbon atoms(butene, pentene, octene, decene, dodecene, tetradodecene and the like)and homopolymers of C₃ to C₁₀, e.g. , C₂ to C₅ monoolefins, andcopolymers of C₂ to C₁₀, e.g., C₂ to C₅ , monoolefins, said additionalpolymer having a number average molecular weight of at least about 900,and a molecular weight distribution of less than about 4.0, preferablyless than about 3.0 (e.g, from 1.2 to 2.8). Preferred such additionalolefin polymers comprise a major molar amount of C₂ to C₁₀, e.g., C₂ toC₅ monoolefin. Such olefins include ethylene, propylene, butylene,isobutylene, pentene, octene-1, styrene, etc. Exemplary of theadditionally charged homopolymers is polypropylene, polyisobutylene, andpoly-n-butene the like as well as interpolymers of two or more of sucholefins such as copolymers of: ethylene and propylene (prepared byconventional methods other than as described above for the preferredethylene alpha-olefin copolymers employed in this invention, that is,ethylene-propylene copolymers which are substantially saturated, whereinless than about 10wt. % of the polymer chains contain ethylenicunsaturation); butylene and isobutylene; propylene and isobutylene; etc.Other copolymers include those in which a minor molar amount of thecopolymer monomers, e.g., 1 to 10 mole %, is a C₄ to C₁₈ non-conjugateddiolefin, e.g., a copolymer of isobutylene and butadiene: or a copolymerof ethylene, propylene and 1,4-hexadiene; etc. The additional sucholefin polymers charged to the alkylation reaction will usually havenumber average molecular weights of at least about 900, more generallywithin the range of about 1200 and about 5,000, more usually betweenabout 1500 and about 4000. Particularly useful such additional olefinpolymers have number average molecular weights within the range of about1500 and about 3000 with approximately one double bond per chain. Anespecially useful additional such polymer is polyisobutylene. Preferredare mixtures of such polyisobutylene with ethylene-propylene copolymerswherein at least 30wt. % of the copolymer chains contain terminalethenylene monounsaturation as described above.

The number average molecular weight for such polymers can be determinedby several known techniques. A convenient method for such determinationis by gel permeation chromatography (GPC) which additionally providesmolecular weight distribution information, see W. W. Yau, J. J. Kirklandand D. D. Bly, "Modern Size Exclusion Liquid Chromatography" John Wileyand Sons New York, 1979.

The Aldehyde Material

The aldehyde reactants will generally comprise formaldehyde orparaformaldehyde, although it will be understood that otheraldehyde-group containing compounds, such as C₂ to C₁₀ hydrocarbylaldehydes (e.g., butyraldehyde, acetaldehyde, propionaldehyde, and thelike) can also be employed. A preferred group of aldehyde materials arecompounds of the formula: R"CHO, wherein R" is H or aliphatichydrocarbon radical having from 1 to 4 carbon atoms.

Amine Compounds

Amine compounds useful as nucleophilic reactants for reaction with theselected ethylene-alpha-olefin polymer and aldehyde materials includemono- and (preferably) polyamines, of about 2 to 60, preferably 2 to 40(e.g. 3 to 20), total carbon atoms and about 1 to 12, preferably 3 to12, and most preferably 3 to 9 nitrogen atoms in the molecule. Theseamines may be hydrocarbyl amines or may be hydrocarbyl amines includingother groups, e.g, hydroxy groups, alkoxy groups, amide groups,nitriles, imidazoline groups, and the like. Hydroxy amines with 1 to 6hydroxy groups, preferably 1 to 3 hydroxy groups are particularlyuseful. Preferred amines are aliphatic saturated amines, including thoseof the general formulas: ##STR3## wherein R, R' , R" and R"' ' areindependently selected from the group consisting of hydrogen; C₁ to C₂₅straight or branched chain alkyl radicals; C₁ to C₁₂ alkoxy C₂ to C₆alkylene radicals; C₂ to C₁₂ hydroxy amino alkylene radicals; and C₁ toC₁₂ alkylamino C₂ to C₆ alkylene radicals; and wherein R" ' canadditionally comprise a moiety of the formula: ##STR4## wherein R' is asdefined above, and wherein r and r' can be the same or a differentnumber of from 2 to 6, preferably 2 to 4; and t and t' can be the sameor different and are numbers of from 0 to 10, preferably 2 to 7, andmost preferably about 3 to 7, with the proviso that the sum of t and t'is not greater than 15. To assure a facile reaction, it is preferredthat R, R' , R" , R"', r, r', t and t' be selected in a mannersufficient to provide the compounds of Formulas IV and V with typicallyat least one primary or secondary amine group, preferably at least twoprimary or secondary amine groups. This can be achieved by selecting atleast one of said R, R', R" or R"' groups to be hydrogen or by letting tin Formula V be at least one when R"' is H or when the VI moietypossesses a secondary amino group. The most preferred amine of the aboveformulas are represented by Formula V and contain at least two primaryamine groups and at least one, and preferably at least three, secondaryamine groups.

Non-limiting examples of suitable amine compounds include:1,2-diaminoethane; 1,3-diaminopropane; 1,4-diaminobutane;1,6-diaminohexane; polyethylene amines such as diethylene triamine;triethylene tetramine; tetraethylene pentamine; polypropylene aminessuch as 1,2-propylene diamine; di-(1,2-propylene)triamine;di-(1,3-propylene) triamine; N,N-dimethyl-1,3-diaminopropane;N,N-di-(2-aminoethyl) ethylene diamine;N,N-di(2-hydroxyethyl)-1,3-propylene diamine; 3-dodecyloxypropylamine;N-dodecyl-1,3-propane diamine; tris hydroxymethylaminomethane (THAM);diisopropanol amine; diethanol amine; triethanol amine; mono-, di-, andtri-tallow amines; amino morpholines such asN-(3-aminopropyl)morpholine; and mixtures thereof.

Other useful amine compounds include: alicyclic diamines such as1,4-di(aminomethyl) cyclohexane, and heterocyclic nitrogen compoundssuch as imidazolines, and N-aminoalkyl piperazines of the genera 1formula (VII): ##STR5## wherein p₁ and p₂ are the same or different andare each integers of from 1 to 4, and n₁, n₂ and n₃ are the same ordifferent and are each integers of from 1 to 3 . Non-limiting examplesof such amines include -pentadecyl imidazoline; N-(2-aminoethyl)piperazine; etc.

Commercial mixtures of amine compounds may advantageously be used. Forexample, one process for preparing alkylene amines involves the reactionof an alkylene dihalide (such as ethylene dichloride or propylenedichloride) with ammonia, which results in a complex mixture of alkyleneamines wherein pairs of nitrogens are joined by alkylene groups, formingsuch compounds as diethylene triamine, triethylenetetramine,tetraethylene pentamine and isomeric piperazines. Low cost poly(ethyleneamines) compounds averaging about 5 to 7 nitrogen atoms permolecule are available commercially under trade names such as "PolyamineH", "Polyamine 400", "Dow Polyamine E-100", etc.

Useful amines also include polyoxyalkylene polyamines such as those ofthe formula (VIII): ##STR6## where m has a value of about 3 to 70 andpreferably 10 to 35; and the formula (IX): ##STR7## where n"' has avalue of about 1 to 40 with the provision that the sum of all the n"'values is from about 3 to about 70 and preferably from about 6 to about35, and R⁴ is a polyvalent saturated hydrocarbon radical of up to tencarbon atoms wherein the number of substituents on the R⁸ group isrepresented by the value of "a", which is a number of from 3 to 6. Thealkylene groups in either formula (VIII) or (IX) may be straight orbranched chains containing about 2 to 7, and preferably about 2 to 4carbon atoms.

The polyoxyalkylene polyamines of formulas (VIII) or (IX) above,preferably polyoxyalkylene diamines and polyoxyalkylene triamines, mayhave average molecular weights ranging from about 200 to about 4000 andpreferably from about 400 to about 2000. The preferred polyoxyalkylenepolyoxyalkylene polyamines include the polyoxyethylene andpolyoxypropylene diamines and the polyoxypropylene triamines havingaverage molecular weights ranging from about 200 to 2000. Thepolyoxyalkylene polyamines are commercially available and may beobtained, for example, from the Jefferson Chemical Company, Inc. underthe trade name "Jeffamines D-230, D-400, D-1000, D-2000, T-403", etc.

A particularly useful class of amines are the polyamido and relatedamines disclosed in U.S. Pat. No. 4,857,217 (the disclosure of which ishereby incorporated by reference in its entirety) which comprisereaction products of a polyamine and an alpha, beta unsaturated compoundof the formula: ##STR8## wherein X is sulfur or oxygen, Y is --OR⁸,--SR⁸, or --NR⁸ (R⁹), and R⁵, R⁶, R⁷, R⁸ and R⁹ are the same ordifferent and are hydrogen or substituted or unsubstituted hydrocarbyl.Any polyamine, whether aliphatic, cycloaliphatic, aromatic,heterocyclic, etc., can be employed provided it is capable of addingacross the acrylic double bond and amidifying with for example thecarbonyl group (--C(O)--) of the acrylate-type compound of formula X, orwith the thiocarbonyl group (--C(S)--) of the thioacrylate-type compoundof formula X.

When R⁵, R⁶, R⁷, R⁸ or R⁹ in Formula X are hydrocarbyl, these groups cancomprise alkyl, cycloalkyl, aryl, alkaryl, aralkyl or heterocyclic,which can be substituted with groups which are substantially inert toany component of the reaction mixture under conditions selected forpreparation of the amido-amine. Such substituent groups include hydroxy,halide (e.g., Cl, Fl, I, Br), --SH and alkylthio. When one or more of R⁵through R⁹ are alkyl, such alkyl groups can be straight or branchedchain, and will generally contain from 1 to 20, more usually from 1 to10, and preferably from 1 to 4, carbon atoms. Illustrative of such alkylgroups are methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl,nonyl, decyl, dodecyl, tridecyl, hexadecyl, octadecyl and the like. Whenone or more of R⁵ through R⁹ are aryl, the aryl group will generallycontain from 6 to 10 carbon atoms (e.g., phenyl, naphthyl).

When one or more of R⁵ through R⁹ are alkaryl, the alkaryl group willgenerally contain from about 7 to 20 carbon atoms, and preferably from 7to 12 carbon atoms. Illustrative of such alkaryl groups are tolyl,m-ethylphenyl, o-ethyltolyl, and m-hexyltolyl. When one or more of R⁵through R⁹ are aralkyl, the aryl component generally consists of phenylor (C₁ to C₆) alkyl-substituted phenol and the alkyl component generallycontains from 1 to 12 carbon atoms, and preferably from 1 to 6 carbonatoms. Examples of such aralkyl groups are benzyl, o-ethylbenzyl, and4-isobutylbenzyl. When one or more of R⁵ and R⁹ are cycloalkyl, thecycloalkyl group will generally contain from 3 to 12 carbon atoms, andpreferably from 3 to 6 carbon atoms. Illustrative of such cycloalkylgroups are cyclopropyl, cyclobutyl, cyclohexyl, cyclooctyl, andcyclododecyl. When one or more of R⁵ through R⁹ are heterocyclic, theheterocyclic group generally consists of a compound having at least onering of 6 to 12 members in which on or more ring carbon atoms isreplaced by oxygen or nitrogen. Examples of such heterocyclic groups arefuryl, pyranyl, pyridyl, piperidyl, dioxanyl, tetrahydrofuryl, pyrazinyland 1,4-oxazinyl.

The alpha, beta ethylenically unsaturated carboxylate compounds employedherein have the following formula: ##STR9## wherein R⁵, R⁶, R⁷, and R⁸are the same or different and are hydrogen or substituted orunsubstituted hydrocarbyl as defined above. Examples of such alpha,beta-ethylenically unsaturated carboxylate compounds of formula XI areacrylic acid, methacrylic acid, the methyl, ethyl, isopropyl, n-butyl,and isobutyl esters of acrylic and methacrylic acids, 2-butenoic acid,2-hexenoic acid, 2-decenoic acid, 3-methyl-2-heptenoic acid,3-methyl-2-butenoic acid, 3-phenyl-2-propenoic acid,3-cyclohexyl-2-butenoic acid, 2-methyl-2-butenoic acid,2-propyl-2-propenoic acid, 2-isopropyl-2-hexenoic acid,3-dimethyl-2-butenoic acid, 3-cyclohexyl-2-methyl-2-pentenoic acid,2-propenoic acid, methyl 2-propenoate, methyl 2-methyl 2-propenoate,methyl 2-butenoate, ethyl 2-hexenoate, isopropyl 2-decenoate, phenyl2-pentenoate, tertiary butyl 2-propenoate, octadecyl 2-propenoate,dodecyl 2-decenoate, cyclopropyl 2,3-dimethyl-2-butenoate, methyl3-phenyl-2-propenoate, and the like.

The alpha, beta ethylenically unsaturated carboxylate thioestercompounds employed herein have the following formula: ##STR10## whereinR⁵, R⁶, R⁷, and R⁸ are the same or different and are hydrogen orsubstituted or unsubstituted hydrocarbyl as defined above. Examples ofsuch alpha, beta-ethylenically unsaturated carboxylate thioesters offormula XII are methylmercapto 2-butenoate, ethylmercapto 2-hexenoate,isopropylmercapto 2-decenoate, phenylmercapto 2-pentenoate, tertiarybutylmercapto 2-propenoate, octadecylmercapto 2-propenoate,dodecylmercapto 2-decenoate, cyclopropylmercapto2,3-dimethyl-2-butenoate, methylmercapto 3-phenyl-2-propenoate,methylmercapto 2-propenoate, methylmercapto 2-methyl-2-propenoate, andthe like.

The alpha, beta ethylenically unsaturated carboxyamide compoundsemployed herein have the following formula: ##STR11## wherein R⁵, R⁶,R⁷, R⁸ and R⁹ are the same or different and are hydrogen or substitutedor unsubstituted hydrocarbyl as defined above. Examples of alpha,beta-ethylenically unsaturated carboxyamides of formula XIII are2-butenamide, 2-hexenamide, 2-decenamide, 3-methyl-2-heptenamide,3-methyl-2-butenamide, 3-phenyl-2-propenamide,3-cyclohexyl-2-butenamide, 2-methyl-2-butenamide,2-propyl-2-propenamide, 2-isopropyl-2-hexenamide,2,3-dimethyl-2-butenamide, 3-cyclohexyl-2-methyl-2-pentenamide, N-methyl2-butenamide, N,N-diethyl 2-hexenamide, N-isopropyl 2-decenamide,N-phenyl 2-pentenamide, N-tertiary butyl 2-propenamide, N-octadecyl2-propenamide, N-N-didodecyl 2-decenamide, N-cyclopropyl2,3-dimethyl-2-butenamide, N-methyl 3-phenyl-2-propenamide,2-propenamide, 2-methyl-2-propenamide, 2-ethyl-2-propenamide and thelike.

The alpha, beta ethylenically unsaturated thiocarboxylate compoundsemployed herein have the following formula: ##STR12## wherein R⁵, R⁶,R⁷, R⁸ and R⁹ are the same or different and are hydrogen or substitutedor unsubstituted hydrocarbyl as defined above. Examples of alpha,beta-ethylenically unsaturated thiocarboxylate compounds of formula XIVare 2-butenthioic acid, 2-hexenthioic acid, 2-decenthioic acid,3-methyl-2-heptenthioic acid, 3-methyl-2-butenthioic acid,3-phenyl-2-propenthioic acid, 3-cyclohexyl -2-butenthioic acid,2-methyl-2-butenthioic acid, 2-propyl-2-propenthioic acid,2-isopropyl-2-hexenthioic acid, 2,3-dimethyl-2-butenthioic acid,3-cyclo-hexyl-2-methyl-2-pententhioic acid, 2-propenthioic acid, methyl2-propenthioate, methyl 2-methyl 2-propenthioate, methyl 2-butenthioate,ethyl 2-hexenthioate, isopropyl 2-decenthioate, phenyl 2-pententhioate,tertiary butyl 2-propenthioate, octadecyl 2-propenthioate, dodecyl2-decenthioate, cyclopropyl 2,3-dimethyl-2-butenthioate, methyl3-phenyl-2-propenthioate, and the like.

The alpha, beta ethylenically unsaturated dithioic acid and acid estercompounds employed herein have the following formula: ##STR13## whereinR⁵, R⁶, R⁷, and R⁸ are the same or different and are hydrogen orsubstituted or unsubstituted hydrocarbyl as defined above. Examples ofalpha, beta-ethylenically unsaturated dithioic acids and acid esters offormula XV are 2-butendithioic acid, 2-hexendithioic acid,2-decendithioic acid, 3-methyl-2-heptendithioic acid,3-methyl-2-butendithioic acid, 3-phenyl-2-propendithioic acid,3-cyclohexyl-2-butendithioic acid, 2-methyl-2-butendithioic acid,2-propyl-2-propendithioic acid, 2-isopropyl-2-hexendithioic acid,2,3-dimethyl-2-butendithioic acid,3-cyclo-hexyl-2-methyl-2-pentendithioic acid, 2-propendithioic acid,methyl 2-propendithioate, methyl 2-methyl 2-propendithioate, methyl2-butendithioate, ethyl 2-hexendithioate, isopropyl 2-decendithioate,phenyl 2-pentendithioate, tertiary butyl 2-propendithioate, octadecyl2-propendithioate, dodecyl 2-decendithioate, cyclopropyl2,3-dimethyl-2-butendithioate, methyl 3-phenyl-2-propendithioate, andthe like.

The alpha, beta ethylenically unsaturated thiocarboxyamide compoundsemployed herein have the following formula: ##STR14## wherein R⁵, R⁶,R⁷, R⁸ and R⁹ are the same or different and are hydrogen or substitutedor unsubstituted hydrocarbyl as defined above. Examples of alpha,beta-ethylenically unsaturated thiocarboxyamides of formula XVI are2-butenthioamide, 2-hexenthioamide, 2-decenthioamide,3-methyl-2-heptenthioamide, 3-methyl-2-butenthioamide,3-phenyl-2-propenthioamide, 3-cyclohexyl-2-butenthioamide,2-methyl-2-butenthioamide, 2-propyl-2-propenthioamide,2-isopropyl-2-hexenthioamide, 2,3-di-methyl-2-butenthioamide,3-cyclohexyl-2-methyl-2-pententhioamide, N-methyl 2-butenthioamide,N,N-diethyl 2-hexenthioamide, N-isopropyl 2-decenthioamide, N-phenyl2-pententhioamide, N-tertiary butyl 2-propenthioamide, N-octadecyl2-propenthioamide, N-N-didodecyl 2-decenthioamide, N-cyclopropyl2,3-dimethyl-2-butenthioamide, N-methyl 3-phenyl-2-propenthioamide,2-propenthioamide, 2-methyl-2-propenthioamide, 2-ethyl-2-propenthioamideand the like.

Preferred compounds for reaction with the polyamines in accordance withthis invention are lower alkyl esters of acrylic and (lower alkyl)substituted acrylic acid. Illustrative of such preferred compounds arecompounds of the formula: ##STR15## where R⁷ is hydrogen or a C₁ to C₄alkyl group, such as methyl, and R⁸ is hydrogen or a C₁ to C₄ alkylgroup, capable of being removed so as to form an amido group, forexample, methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl,aryl, hexyl, etc. In the preferred embodiments these compounds areacrylic and methacrylic esters such as methyl or ethyl acrylate, methylor ethyl methacrylate. When the selected alpha, beta-unsaturatedcompound comprises a compound of formula X wherein X' is oxygen, theresulting reaction product with the polyamine contains at least oneamido linkage (--C(O)N<) and such materials are herein termed"amido-amines." Similarly, when the selected alpha, beta unsaturatedcompound of formula X comprises a compound wherein X' is sulfur, theresulting reaction product with the polyamine contains thioamide linkage(--C(S)N<) and these materials are herein termed "thioamido-amines." Forconvenience, the following discussion is directed to the preparation anduse of amido-amines, although it will be understood that such discussionis also applicable to the thioamido-amines.

The type of amido-amine formed varies with reaction conditions. Forexample, a more linear amido-amine is formed where substantiallyequimolar amounts of the unsaturated carboxylate and polyamine arereacted. The presence of excesses of the ethylenically unsaturatedreactant of formula X tends to yield an amido-amine which is morecross-linked than that obtained where substantially equimolar amounts ofreactants are employed. Where for economic or other reasons across-linked amido-amine using excess amine is desired, generally amolar excess of the ethylenically unsaturated reactant of about at least10%, such as 10-300%, or greater, for example, 25-200%, is employed. Formore efficient cross-linking an excess of carboxylated material shouldpreferably be used since a cleaner reaction ensues. For example, a molarexcess of about 10-100% or greater such as 10-50%, but preferably anexcess of 30-50%, of the carboxylated material. Larger excess can beemployed if desired.

In summary, without considering other factors, equimolar amounts ofreactants tend to produce a more linear amido-amine whereas excess ofthe formula XII reactant tends to yield a more cross-linked amido-amine.It should be noted that the higher the polyamine (i.e., in greater thenumber of amino groups on the molecule) the greater the statisticalprobability of cross-linking since, for example, atetraalkylenepentamine, such as tetraethylene pentamine ##STR16## hasmore labile hydrogens than ethylene diamine.

These amido-amine adducts so formed are characterized by both amido andamino groups. In their simplest embodiments they may be represented byunits of the following idealized formula (XVIII): ##STR17## wherein theR¹⁰ 's, which may be the same or different, are hydrogen or asubstituted group, such as a hydrocarbon group, for example, alkyl,alkenyl, alkynyl, aryl, etc., and A is a moiety of the polyamine which,for example, may be aryl, cycloalkyl, alkyl, etc., and n₄ is an integersuch as 1-10 or greater.

The above simplified formula represents a linear amido-amine polymer.However, cross-linked polymers may also be formed by employing certainconditions since the polymer has labile hydrogens which can furtherreact with either the unsaturated moiety by adding across the doublebond or by amidifying with a carboxylate group.

Preferably, however, the amido-amines employed in this invention are notcross-linked to any substantial degree, and more preferably aresubstantially linear.

Preferably, the polyamine reactant contains at least one primary amine(and more preferably from 2 to 4 primary amines) group per molecule, andthe polyamine and the unsaturated reactant of formula X are contacted inan amount of from about 1 to 10, more preferably from about 2 to 6, andmost preferably from about 3 to 5, equivalents of primary amine in thepolyamine reactant per mole of the unsaturated reactant of formula X.

The reaction between the selected polyamine and acrylate-type compoundis carried out at any suitable temperature. Temperatures up to thedecomposition points of reactants and products can be employed. Inpractice, one generally carries out the reaction by heating thereactants below 100° C., such as 80°-90° C., for a suitable period oftime, such as a few hours. Where an acrylic-type ester is employed, theprogress of the reaction can be judged by the removal of the alcohol informing the amide. During the early part of the reaction alcohol isremoved quite readily below 100° C. in the case of low boiling alcoholssuch as methanol or ethanol. As the reaction slows, the temperature israised to push the polymerization to completion and the temperature maybe raised to 150° C. toward the end of the reaction. Removal of alcoholis a convenient method of judging the progress and completion of thereaction which is generally continued until no more alcohol is evolved.Based on removal of alcohol, the yields are generally stoichiometric. Inmore difficult reactions, yield of at least 95% are generally obtained.

Similarly, it will be understood that the reaction of an ethylenicallyunsaturated carboxylate thioester of formula XII liberates thecorresponding HSR⁸ compound (e.g., H₂ S when R⁸ is hydrogen) as aby-product, and the reaction of an ethylenically unsaturatedcarboxyamide of formula XIII liberates the corresponding HNR⁸ (R⁹)compound (e.g., ammonia when R⁸ and R⁹ are each hydrogen) as by-product.

The reaction time to form an amido-amine material can vary widelydepending on a wide variety of factors. For example, there is arelationship between time and temperature. In general, lower temperaturedemands longer times. Usually, reaction times of from about 2 to 30hours, such as 5 to 25 hours, and preferably 3 to 10 hours will beemployed. Although one can employ a solvent, the reaction can be runwithout the use of any solvent. In fact, where a high degree ofcross-linking is desired, it is preferably to avoid the use of a solventand most particularly to avoid a polar solvent such as water. However,taking into consideration the effect of solvent on the reaction, wheredesired, any suitable solvent can be employed, whether organic orinorganic, polar or non-polar.

As an example of the amido-amine adducts, the reaction of tetraethylenepentaamine (TEPA) with methyl methacrylate can be illustrated asfollows: ##STR18##

Condensation Reaction

The Mannich Base condensate dispersants of this invention are preparedby condensing at least one of the above described alkylatedhydroxyaromatic compounds with an amine in the presence of an aldehyde.The reactants are contacted for a time and under conditions sufficientto form the desired dispersant product.

The process employed in the condensation reaction can be any of thosedisclosed in U.S. Pat. Nos. 3,634,515; 3,649,229; 3,442,808; 3,798,165;3,798,247; and 3,539,633, the disclosures of which are herebyincorporated by reference in their entirety.

The amount of the reactants employed is not critical and can vary over awide range. It is, however, preferred to react the alkylated hydroxyaromatic compound, aldehyde reactant and amine compound in therespective molar ratios of about 1:1-4:0.1-10. An excess of aldehydereactant may be used. The reactions are exothermic, but it is desirableto heat the reaction to a temperature of above about 150° C., preferablyin the range of form about 150°-200° C. This additional heating drivesthe reaction to completion and removes water from the resultantcondensation reaction product.

The condensation reaction can be illustrated by the following reactionsemploying an alkylene polyamine and formaldehyde: ##STR19## wherein "z"is an integer of from 1 to 10, "a" is an integer of 1 or 2 and "EP" isan ethylene-propylene copolymer as described above, and ##STR20##wherein "z" and "EP" are as defined above

A preferred group of Mannich Base ashless dispersants are those formedby condensing ethylene-propylene copolymer-substituted phenol withformaldehyde and polyethylene amines, e.g., tetraethylene pentamine,pentaethylene hexamine, polyoxyethylene and polyoxypropylene amines,e.g., polyoxypropylene diamine, and combinations thereof. Oneparticularly preferred dispersant comprises a condensation of (A)ethylene-propylene copolymer-substituted phenol, (B) formaldehyde, (C) apolyoxyalkylene polyamine, e.g., polyoxypropylene diamine, and (D) apolyalkylene polyamine, e.g. polyethylene diamine and tetraethylenepentamine, using about 2 to about 8 moles each of (B) and about 1 toabout 4 moles of (C) or (D) per mole of (A).

The reaction product mixture comprising the desiredethylene-alpha-olefin substituted Mannich Base condensation productformed by the process of this invention will generally be present in thecondensation reaction product mixture in a concentration of at leastabout 60wt. % (e.g., from 65 to 95wt. %), more preferably at least about70wt. %, from 75 to 90wt. %, and will be generally characterized by a VRvalue ("viscosity ratio" value) of not greater than about 4.1, usuallynot greater than about 4.0, preferably from about 2.5 to 4.0, and mostpreferably from about 3.0 to 3.9. As used herein, the term "VR value" isintended to mean quotient determined by the expression (IV): ##EQU1##wherein VISa is the kinematic viscosity (KV) of the condensationreaction product mixture at 100° C. in units of centistokes (asdetermined by ASTM Method No. D445) and VISb is the cold crankingsimulator (CCS) viscosity of the condensation reaction product mixtureat -20° C. in units of poise (as determined by ASTM Method No. D2602),wherein the measurements are made upon a 2wt. % solution of thecondensation reaction product mixture in an oil (herein termed the"reference oil") comprising S150N (solvent 150 neutral) minerallubricating oil (Exxon Company U.S.A.), wherein the such reference oilis characterized by an ASTM D445 kinematic viscosity of 5.2 cSt (100°C.) and an ASTM D2602 CCS viscosity of 19.2 poise (±0.4 poise) (at -20°C.). The "VRr" value of the reference oil will then be about 3.7±0.1.

Another aspect of this invention involves the post treatment of thenitrogen containing dispersant materials. The process for post-treatingsaid nitrogen containing dispersant materials is analogous to thepost-treating processes used with respect to derivatives of conventionalethylene copolymers of the prior art. Accordingly, the same reactionconditions, ratio of reactants and the like can be used.

The nitrogen-containing dispersant materials of the instant invention asdescribed above are post-treated by contacting said nitrogen-containingdispersant materials with one or more post-treating reagents selectedfrom the group consisting of boron oxide, boron oxide hydrate, boronhalides, boron acids, esters of boron acids, carbon disulfide, sulfur,sulfur chlorides, alkenyl cyanides, aldehydes, ketones, urea, thio-urea,guanidine, dicyanodiamide, hydrocarbyl phosphates, hydrocarbylphosphites, hydrocarbyl thiophosphates, hydrocarbyl thiophosphites,phosphorus sulfides, phosphorus oxides, phosphoric acid, hydrocarbylthiocyanates, hydrocarbyl isocyanates, hydrocarbyl isothiocyantes,epoxides, episulfides, formaldehyde or formaldehyde-producing compoundsplus phenols, and sulfur plus phenols, and C₁ to C₃₀ hydrocarbylsubstituted succinic acids and anhydrides (e.g., succinic anhydride,dodecyl succinic anhydride and the like), fumaric acid, itaconic acid,maleic acid, maleic anhydride, chloromaleic acid, chloromaleicanhydride, acrylic acid, methacrylic acid, crotonic acid, cinnamic acid,and lower alkyl (e.g., C₁ to C₄ alkyl) acid esters of the foregoing,e.g., methyl maleate, ethyl fumarate, methyl fumarate, and the like.

For example, the nitrogen containing dispersants can be treated with aboron compound selected from the class consisting of boron oxide, boronhalides, boron acids and esters of boron acids in an amount to providefrom about 0.1 atomic proportion of boron for each mole of said nitrogencomposition to about 20 atomic proportions of boron for each atomicproportion of nitrogen of said nitrogen composition. Usefully theborated dispersants of the invention contain from about 0.05 to 2.0wt.%, e.g. 0.05 to 0.7wt. % boron based on the total weight of said boratednitrogen-containing dispersant compound. The boron, which appears to bein the product as dehydrated boric acid polymers (primarily (HBO₂)₃), isbelieved to attach to the dispersant as amine salts, e.g., themetaborate salt of said amine dispersants.

Treating is readily carried out by adding from about 0.05 to 4, e.g. 1to 3wt. % (based on the weight of said nitrogen compound) of said boroncompound, preferably boric acid which is most usually added as a slurryto said nitrogen compound and heating with stirring at from about 135°C. to 190°, e.g. 140°-170° C., for from 1 to 5 hours followed bynitrogen stripping at said temperature ranges.

Since post-treating processes involving the use of these post-treatingreagents is known insofar as application to high molecular weightnitrogen containing dispersants of the prior art, further descriptionsof these processes herein is unnecessary. In order to apply the priorart processes to the compositions of this invention, all that isnecessary is that reaction conditions, ratio of reactants, and the likeas described in the prior art, be applied to the novel compositions ofthis invention. The following U.S. patents are expressly incorporatedherein by reference for their disclosure of post-treating processes andpost-treating reagents applicable to the compositions of this invention:U.S. Pat. Nos. 3,087,936; 3,200,107 3,254,025; 3,256,185; 3,278,550;3,281,428; 3,282,955; 3,284,410; 3,338,832, 3,344,069; 3,366,569;3,373,111; 3,367,943; 3,390,086; 3,403,102; 3,428,561; 3,470,098;3,502,677; 3,513,093; 3,533,945; 3,541,012; 3,558,743; 3,639,242;3,708,522; 3,859,318; 3,865,813; 3,470,098; 3,369,021; 3,184,411;3,185,645; 3,245,908; 3,245,909; 3,245,910; 3,573,205; 3,692,681;3,749,695; 3,865,740; 3,954,639; 3,458,530; 3,390,086; 3,367,943;3,185,704, 3,551,466; 3,415,750; 3,312,619; 3,280,034; 3,718,663;3,652,616; 4,338,205; 4,428,849; 4,686,054; 4,839,070; 4,839,071;4,839,072; 4,839,073; U.K. Pat. No. 1,085,903; U.K. Pat. No. 1,162,436.

The nitrogen containing dispersant materials of this invention can alsobe treated with polymerizable lactones (such as epsilon-caprolactone) toform dispersant adducts having the moiety --[C(O)(CH₂)_(z) O]_(m) H,wherein z is a number of from 4 to 8 (e.g., 5 to 7) and m has an averagevalue of from about 0 to 100 (e.g., 0.2 to 20). The dispersants of thisinvention can be post-treated with a C₅ to C₉ lactone, e.g.,epsilon-caprolactone, by heating a mixture of the dispersant materialand lactone in a reaction vessel in the absence of a solvent at atemperature of about 50° C. to about 200° C., more preferably from about75° C. to about 180° C., and most preferably from about 90° C. to about160° C., for a sufficient period of time to effect reaction. Optionally,a solvent for the lactone, dispersant material and/or the resultingadduct may be employed to control viscosity and/or the reaction rates.

In one preferred embodiment, the C₅ to C₉ lactone, e.g.,epsilon-caprolactone, is reacted with a dispersant material in a 1:1mole ratio of lactone to dispersant material. In practice, the ration oflactone to dispersant material may vary considerably as a means ofcontrolling the length of the sequence of the lactone units in theadduct. For example, the mole ratio of the lactone to the dispersantmaterial may vary from about 10:1 to about 0.1:1, more preferably fromabout 5:1 to about 0.2:1, and most preferably from about 2:1 to about0.4:1. It is preferable to maintain the average degree of polymerizationof the lactone monomer below about 100, with a degree of polymerizationon the order of from about 0.2 to about 50 being preferred, and fromabout 0.2 to about 20 being more preferred. For optimum dispersantperformance, sequences of from about 1 to about 5 lactone units in a roware preferred.

Catalysts useful in the promotion of the lactone-dispersant materialreactions are selected from the group consisting of stannous octanoate,stannous hexanoate, tetrabutyl titanate, a variety of organic based acidcatalysts and amine catalysts, as described on page 266, and forward, ina book chapter authored by R. D. Lundberg and E. F. Cox, entitled"Kinetics and Mechanisms of Polymerization: Ring OpeningPolymerization", edited by Frisch and Reegen, published by Marcel Dekkerin 1969, wherein stannous octanoate is an especially preferred catalyst.The catalyst is added to the reaction mixture at a concentration levelof about 50 to about 10,000 parts per weight of catalyst per one millionparts of the total reaction mixture.

Exemplary of adducts formed by reaction of dispersant materials if thisinvention and epsiloncaprolactone are those adducts illustrated by thefollowing equation: ##STR21## wherein m and EP are as defined above. Thereactions of such lactones with dispersant materials containing nitrogenor ester groups is more completely described in U.S. Pat. Nos.4,486,326; 4,820,432; 4,828,742; 4,851,524; 4,866,135; 4,866,139;4,866,140; 4,866,141; 4,866,142; and 4,866,187, the disclosure of eachof which is hereby incorporated by reference in its entirety.

Further aspects of the present invention reside in the formation ofmetal complexes of the novel dispersant additives prepared in accordancewith this invention. Suitable metal complexes may be formed inaccordance with known techniques of employing a reactive metal ionspecies during or after the formation of the present dispersantmaterials. Complex forming metal reactants include the metal nitrates,thiocyanates, halides, carboxylates, phosphates, thio-phosphates,sulfates, and borates of transition metals such as iron, cobalt, nickel,copper, chromium, manganese, molybdenum, tungsten, ruthenium, palladium,platinum, cadmium, lead, silver, mercury, antimony and the like. Priorart disclosures of these complexing reactions may be also found in U.S.Pat. No. 3,306,908 and Re. 26,433, the disclosures of which are herebyincorporated by reference in their entirety.

The processes of these incorporated patents, as applied to thecompositions of this invention, and the post-treated compositions thusproduced constitute a further aspect of this invention.

The dispersants of the present invention can be incorporated into alubricating oil in any convenient way. Thus, these mixtures can be addeddirectly to the oil by dispersing or dissolving the same in the oil atthe desired level of concentrations of the dispersant and detergent,respectively. Such blending into the additional lube oil can occur atroom temperature or elevated temperatures. Alternatively, thedispersants can be blended with a suitable oil-soluble solvent and baseoil to form a concentrate, and then blending the concentrate with alubricating oil basestock to obtain the final formulation. Suchdispersant concentrates will typically contain (on an active ingredient(A.I.) basis) from about 20 to about 60 wt. %, and preferably from about40 to about 50wt. %, dispersant additive, and typically from about 40 to80 wt. %, preferably from about 40 to 60wt. %, base oil, based on theconcentrate weight. The lubricating oil basestock for the dispersanttypically is adapted to perform a selected function by the incorporationof additional additives therein to form lubricating oil compositions(i.e., formulations).

Lubricating Compositions

The additive mixtures of the present invention possess very gooddispersant properties as measured herein in a wide variety ofenvironments. Accordingly, the additive mixtures are used byincorporation and dissolution into an oleaginous material such as fuelsand lubricating oils. When the additive mixtures of this invention areused in normally liquid petroleum fuels such as middle distillatesboiling from about 65 ° to 430 ° C., including kerosene, diesel fuels,home heating fuel oil, jet fuels, etc., a concentration of the additivesin the fuel in the range of typically from about 0.001 to about 0.5, andpreferably 0.005 to about 0.15 weight percent, based on the total weightof the composition, will usually be employed.

The additive mixtures of the present invention find their primaryutility in lubricating oil compositions which employ a base oil in whichthe additives are dissolved or dispersed. Such base oils may be naturalor synthetic. Base oils suitable for use in preparing the lubricatingoil compositions of the present invention include those conventionallyemployed as crankcase lubricating oils for spark-ignited andcompression-ignited internal combustion engines, such as automobile andtruck engines, marine and railroad diesel engines, and the like.Advantageous results are also achieved by employing the additivemixtures of the present invention in base oils conventionally employedin and/or adapted for use as power transmitting fluids, universaltractor fluids and hydraulic fluids, heavy duty hydraulic fluids, powersteering fluids and the like. Gear lubricants, industrial oils, pumpoils and other lubricating oil compositions can also benefit from theincorporation therein of the additive mixtures of the present invention.

These lubricating oil formulations conventionally contain severaldifferent types of additives that will supply the characteristics thatare required in the formulations. Among these types of additives areincluded viscosity index improvers, antioxidants, corrosion inhibitors,detergents, dispersants, pour point depressants, antiwear agents,friction modifiers, etc.

In the preparation of lubricating oil formulations it is common practiceto introduce the additives in the form of 10 to 80wt. %, e.g., 20 to80wt. % active ingredient concentrates in hydrocarbon oil, e.g. minerallubricating oil, or other suitable solvent. Usually these concentratesmay be diluted with 3 to 100, e.g., 5 to 40 parts by weight oflubricating oil, per part by weight of the additive package, in formingfinished lubricants, e.g. crankcase motor oils. The purpose ofconcentrates, of course, is to make the handling of the variousmaterials less difficult and awkward as well as to facilitate solutionor dispersion in the final blend. Thus, a dispersant would be usuallyemployed in the form of a 40 to 50wt. % concentrate, for example, in alubricating oil fraction.

The ashless dispersants of the present invention will be generally usedin admixture with a lube oil basestock, comprising an oil of lubricatingviscosity, including natural and synthetic lubricating oils and mixturesthereof.

Natural oils include animal oils and vegetable oils (e.g., castor, lardoil) liquid petroleum oils and hydrorefined, solvent-treated oracid-treated mineral lubricating oils of the paraffinic, naphthenic andmixed paraffinic-naphthenic types. Oils of lubricating viscosity derivedfrom coal or shale are also useful base oils.

Alkylene oxide polymers and interpolymers and derivatives thereof wherethe terminal hydroxyl groups have been modified by esterification,etherification, etc., constitute another class of known syntheticlubricating oils. These are exemplified by polyoxyalkylene polymersprepared by polymerization of ethylene oxide or propylene oxide, thealkyl and aryl ethers of these polyoxyalkylene polymers (e.g.,methyl-poly isopropylene glycol ether having an average molecular weightof 1000, diphenyl ether of poly-ethylene glycol having a molecularweight of 500-1000, diethyl ether of polypropylene glycol having amolecular weight of 1000-1500); and mono- and polycarboxylic estersthereof, for example, the acetic acid esters, mixed C₃ -C₈ fatty acidesters and C₁₃ Oxo acid diester of tetraethylene glycol.

Another suitable class of synthetic lubricating oils comprises theesters of dicarboxylic acids (e.g., phthalic acid, succinic acid, alkylsuccinic acids and alkenyl succinic acids, maleic acid, azelaic acid,suberic acid, sebasic acid, fumaric acid, adipic acid, linoleic aciddimer, malonic acid, alkylmalonic acids, alkenyl malonic acids) with avariety of alcohols (e.g., butyl alcohol, hexyl alcohol, dodecylalcohol, 2-ethylhexyl alcohol, ethylene glycol, diethylene glycolmonoether, propylene glycol). Specific examples of these esters includedibutyl adipate, di(2-ethylhexyl)sebacate, di-n-hexyl fumarate, dioctylsebacate, diisooctyl azelate, diisodecyl azelate, dioctyl phthalate,didecyl phthalate, dieicosyl sebacate, the 2-ethylhexyl diester oflinoleic acid dimer, and the complex ester formed by reacting one moleof sebacic acid with two moles of tetraethylene glycol and two moles of2-ethylhexanoic acid.

Esters useful as synthetic oils also include those made from C₅ to C₁₂monocarboxylic acids and polyols and polyol ethers such as neopentylglycol, trimethylolpropane, pentaerythritol, dipentaerythritol andtripentaerythritol.

Silicon-based oils such as the polyalkyl-, polyaryl-, polyalkoxy-, orpolyaryloxysiloxane oils and silicate oils comprise another useful classof synthetic lubricants; they include tetraethyl silicate,tetraisopropyl silicate, tetra-(2-ethylhexyl) silicate,tetra-(4-methyl-2-ethylhexyl) silicate, tetra-(p-tertbutylphenyl)silicate, hexa-(4-methyl-2-pentoxy)disiloxane, poly(methyl) siloxanes and poly(methylphenyl) siloxanes. Other syntheticlubricating oils include liquid esters of phosphorus-containing acids(e.g., tricresyl phosphate, trioctyl phosphate, diethyl ester ofdecylphosphonic acid) and polymeric tetrahydrofurans.

Unrefined, refined and rerefined oils can be used in the lubricants ofthe present invention. Unrefined oils are those obtained directly from anatural or synthetic source without further purification treatment. Forexample, a shale oil obtained directly from retorting operations, apetroleum oil obtained directly from distillation or ester oil obtaineddirectly from an esterification process and used without furthertreatment would be an unrefined oil. Refined oils are similar to theunrefined oils except they have been further treated in one or morepurification steps to improve one or more properties. Many suchpurification techniques, such as distillation, solvent extraction, acidor base extraction, filtration and percolation are known to thoseskilled in the art. Rerefined oils are obtained by processes similar tothose used to obtain refined oils applied to refined oils which havebeen already used in service. Such rerefined oils are also known asreclaimed or reprocessed oils and often are additionally processed bytechniques for removal of spent additives and oil breakdown products.

Metal containing rust inhibitors and/or detergents are frequently usedwith ashless dispersants. Such detergents and rust inhibitors includethe metal salts of sulphonic acids, alkyl phenols, sulphurized alkylphenols, alkyl salicylates, naphthenates, and other oil soluble mono-and di-carboxylic acids. Highly basic, that is overbased metal saltswhich are frequently used as detergents appear particularly prone tointeraction with the ashless dispersant. Usually these metal containingrust inhibitors and detergents are used in lubricating oil in amounts ofabout 0.01 to 10, e.g. 0.1 to 5wt. %, based on the weight of the totallubricating composition. Marine diesel lubricating oils typically employsuch metal-containing rust inhibitors and detergents in amounts of up toabout 20wt. %.

Highly basic alkaline earth metal sulfonates are frequently used asdetergents. They are usually produced by heating a mixture comprising anoil-soluble sulfonate or alkaryl sulfonic acid, with an excess ofalkaline earth metal compound above that required for completeneutralization of any sulfonic acid present and thereafter forming adispersed carbonate complex by reacting the excess metal with carbondioxide to provide the desired overbasing. The sulfonic acids aretypically obtained by the sulfonation of alkyl substituted aromatichydrocarbons such as those obtained from the fractionation of petroleumby distillation and/or extraction or by the alkylation of aromatichydrocarbons as for example those obtained by alkylating benzene,toluene, xylene, naphthalene, diphenyl and the halogen derivatives suchas chlorobenzene, chlorotoluene and chloronaphthalene. The alkylationmay be carried out in the presence of a catalyst with alkylating agentshaving from about 3 to more than 30 carbon atoms. For examplehaloparaffins, olefins obtained by dehydrogenation of paraffins,polyolefins produced from ethylene, propylene, etc. are all suitable.The alkaryl sulfonates usually contain from about 9 to about 70 or morecarbon atoms, preferably from about 16 to about 50 carbon atoms peralkyl substituted aromatic moiety.

The alkaline earth metal compounds which may be used in neutralizingthese alkaryl sulfonic acids to provide the sulfonates includes theoxides and hydroxides, alkoxides, carbonates, carboxylate, sulfide,hydrosulfide, nitrate, borates and ethers of magnesium, calcium, andbarium. Examples are calcium oxide, calcium hydroxide, magnesium acetateand magnesium borate. As noted, the alkaline earth metal compound isused in excess of that required to complete neutralization of thealkaryl sulfonic acids. Generally, the amount ranges from about 100 to220%, although it is preferred to use at least 125%, of thestoichiometric amount of metal required for complete neutralization.

Various other preparations of basic alkaline earth metal alkarylsulfonates are known, such as U.S. Pat. Nos. 3,150,088 and 3,150,089wherein overbasing is accomplished by hydrolysis of analkoxide-carbonate complex with the alkaryl sulfonate in a hydrocarbonsolvent-diluent oil.

A preferred alkaline earth sulfonate additive is magnesium alkylaromatic sulfonate having a total base number ranging from about 300 toabout 400 with the magnesium sulfonate content ranging from about 25 toabout 32 wt. %, based upon the total weight of the additive systemdispersed in mineral lubricating oil.

Neutral metal sulfonates are frequently used as rust inhibitors.Polyvalent metal alkyl salicylate and naphthenate materials are knownadditives for lubricating oil compositions to improve their hightemperature performance and to counteract deposition of carbonaceousmatter on pistons (U.S. Pat. No. 2,744,069). An increase in reservebasicity of the polyvalent metal alkyl salicylates and naphthenates canbe realized by utilizing alkaline earth metal, e.g. calcium, salts ofmixtures of C₈ -C₂₆ alkyl salicylates and phenates (see U.S. Pat. No.2,744,069) or polyvalent metal salts of alkyl salicyclic acids, saidacids obtained from the alkylation of phenols followed by phenation,carboxylation and hydrolysis (U.S. Pat. No. 3,704,315) which could thenbe converted into highly basic salts by techniques generally known andused for such conversion. The reserve basicity of these metal-containingrust inhibitors is usefully at TBN levels of between about 60 and 150.Included with the useful polyvalent metal salicylate and naphthenatematerials are the methylene and sulfur bridged materials which arereadily derived from alkyl substituted salicylic or naphthenic acids ormixtures of either or both with alkyl substituted phenols. Basicsulfurized salicylates and a method for their preparation is shown inU.S. Pat. No. 3,595,791. Such materials include alkaline earth metal,particularly magnesium, calcium, strontium and barium salts of aromaticacids having the general formula:

    HOOC--ArR.sub.l --Xy(ArR.sub.l OH).sub.n                   (XIII)

where Ar is an aryl radical of 1 to 6 rings, R₁ is an alkyl group havingfrom about 8 to 50 carbon atoms, preferably 12 to 30 carbon atoms(optimally about 12), X is a sulfur (--S--) or methylene (--CH₂ --)bridge, y is a number from 0 to 4 and n is a number from 0 to 4.

Preparation of the overbased methylene bridged salicylate-phenate saltis readily carried out by conventional techniques such as by alkylationof a phenol followed by phenation, carboxylation, hydrolysis, methylenebridging using a coupling agent such as an alkylene dihalide followed bysalt formation concurrent with carbonation. An overbased calcium salt ofa methylene bridged phenol-salicylic acid of the general formula (XIV):##STR22## with a TBN of 60 to 150 is highly useful in this invention.

The sulfurized metal phenates can be considered the "metal salt of aphenol sulfide" which thus refers to a metal salt whether neutral orbasic, of a compound typified by the general formula (XV): ##STR23##where x=1 or 2, n=0, 1 or 2; or a polymeric form of such a compound,where R is an alkyl radical, n and x are each integers from 1 to 4, andthe average number of carbon atoms in all of the R groups is at leastabout 9 in order to ensure adequate solubility in oil. The individual Rgroups may each contain from 5 to 40, preferably 8 to 20, carbon atoms.The metal salt is prepared by reacting an alkyl phenol sulfide with asufficient quantity of metal containing material to impart the desiredalkalinity to the sulfurized metal phenate.

Regardless of the manner in which they are prepared, the sulfurizedalkyl phenols which are useful generally contain from about 2 to about14% by weight, preferably about 4 to about 12wt. % sulfur based on theweight of sulfurized alkyl phenol.

The sulfurized alkyl phenol may be converted by reaction with a metalcontaining material including oxides, hydroxides and complexes in anamount sufficient to neutralize said phenol and, if desired, to overbasethe product to a desired alkalinity by procedures well known in the art.Preferred is a process of neutralization utilizing a solution of metalin a glycol ether.

The neutral or normal sulfurized metal phenates are those in which theratio of metal to phenol nucleus is about 1:2. The "overbased" or"basic" sulfurized metal phenates are sulfurized metal phenates whereinthe ratio of metal to phenol is greater than that of stoichiometric,e.g. basic sulfurized metal dodecyl phenate has a metal content up toand greater than 100% in excess of the metal present in thecorresponding normal sulfurized metal phenates wherein the excess metalis produced in oil-soluble or dispersible form (as by reaction withCO₂).

Magnesium and calcium containing additives although beneficial in otherrespects can increase the tendency of the lubricating oil to oxidize.This is especially true of the highly basic sulphonates.

According to a preferred embodiment the invention therefore provides acrankcase lubricating composition also containing from 2 to 8000 partsper million of calcium or magnesium.

The magnesium and/or calcium is generally present as basic or neutraldetergents such as the sulphonates and phenates, our preferred additivesare the neutral or basic magnesium or calcium sulphonates. Preferablythe oils contain from 500 to 5000 parts per million of calcium ormagnesium. Basic magnesium and calcium sulphonates are preferred.

As indicated earlier, a particular advantage of the novel dispersants ofthe present invention is use with V.I. improvers to form multi-gradeautomobile engine lubricating oils. Viscosity modifiers impart high andlow temperature operability to the lubricating oil and permit it toremain relatively viscous at elevated temperatures and also exhibitacceptable viscosity or fluidity at low temperatures. Viscositymodifiers are generally high molecular weight hydrocarbon polymersincluding polyesters. The viscosity modifiers may also be derivatized toinclude other properties or functions, such as the addition ofdispersancy properties. These oil soluble viscosity modifying polymerswill generally have number average molecular weights of from10³ to 10⁶,preferably 10⁴ to 10⁶, e.g., 20 000 to 250,000, as determined by gelpermeation chromatography or osmometry.

Examples of suitable hydrocarbon polymers include homopolymers andcopolymers of two or more monomers of C₂ to C₃₀, e.g. C₂ to C₈ olefins,including both alpha olefins and internal olefins, which may be straightor branched, aliphatic, aromatic, alkyl-aromatic, cycloaliphatic, etc.Frequently they will be of ethylene with C₃ to C₃₀ olefins, particularlypreferred being the copolymers of ethylene and propylene. Other polymerscan be used such as polyisobutylenes, homopolymers and copolymers of C₆and higher alpha olefins, atactic polypropylene, hydrogenated polymersand copolymers and terpolymers of styrene, e.g. with isoprene and/orbutadiene and hydrogenated derivatives thereof. The polymer may bedegraded in molecular weight, for example by mastication, extrusion,oxidation or thermal degradation, and it may be oxidized and containoxygen. Also included are derivatized polymers such as post-graftedinterpolymers of ethylene-propylene with an active monomer such asmaleic anhydride which may be further .reacted with an alcohol, oramine, e.g. an alkylene polyamine or hydroxy amine, e.g. see U.S. Pat.Nos. 4,089,794; 4,160,739; 4,137,185; or copolymers of ethylene andpropylene reacted or grafted with nitrogen compounds such as shown inU.S. Pat. Nos. 4,068,056; 4,068,058; 4,146,489 and 4,149,984.

The preferred hydrocarbon polymers are ethylene copolymers containingfrom 15 to 90wt. % ethylene, preferably 30 to 80wt. % of ethylene and 10to 85wt. %, preferably 20 to 70wt. % of one or more C₃ to C₂₈,preferably C₃ to C₁₈, more preferably C₃ to C₈, alpha-olefins. While notessential, such copolymers preferably have a degree of crystallinity ofless than 25 wt. %, as determined by X-ray and differential scanningcalorimetry. Copolymers of ethylene and propylene are most preferred.Other alpha-olefins suitable in place of propylene to form thecopolymer, or to be used in combination with ethylene and propylene, toform a terpolymer, tetrapolymer, etc., include 1-butene, 1-pentene,1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, etc.; also branchedchain alpha-olefins, such as 4-methyl-1-pentene, 4-methyl-1-hexene,5-methylpentene-1, 4,4-dimethyl-1-pentene, and 6-methylheptene-1, etc.,and mixtures thereof.

Terpolymers, tetrapolymers, etc., of ethylene, said C₃₋₂₈ alpha-olefin,and a non-conjugated diolefin or mixtures of such diolefins may also beused. The amount of the non-conjugated diolefin generally ranges fromabout 0.5 to 20 mole percent, preferably from about 1 to about 7 molepercent, based on the total amount of ethylene and alpha-olefin present.

The polyester V.I. improvers are generally polymers of esters ofethylenically unsaturated C₃ to C₈ mono- and dicarboxylic acids such asmethacrylic and acrylic acids, maleic acid, maleic anhydride, fumaricacid, etc.

Examples of unsaturated esters that may be used include those ofaliphatic saturated mono alcohols of at least 1 carbon atom andpreferably of from 12 to 20 carbon atoms, such as decyl acrylate, laurylacrylate, stearyl acrylate, eicosanyl acrylate, docosanyl acrylate,decyl methacrylate, diamyl fumarate, lauryl methacrylate, cetylmethacrylate, stearyl methacrylate, and the like and mixtures thereof.

Other esters include the vinyl alcohol esters of C₂ to C₂₂ fatty or monocarboxylic acids, preferably saturated such as vinyl acetate, vinyllaurate, vinyl palmitate, vinyl stearate, vinyl oleate, and the like andmixtures thereof. Copolymers of vinyl alcohol esters with unsaturatedacid esters such as the copolymer of vinyl acetate with dialkylfumarates, can also be used.

The esters may be copolymerized with still other unsaturated monomerssuch as olefins, e.g. 0.2 to 5 moles of C₂ -C₂₀ aliphatic or aromaticolefin per mole of unsaturated ester, or per mole of unsaturated acid oranhydride followed by esterification. For example, copolymers of styrenewith maleic anhydride esterified with alcohols and amines are known,e.g., see U.S. Pat. No. 3,702,300.

Such ester polymers may be grafted with, or the ester copolymerizedwith, polymerizable unsaturated nitrogen-containing monomers to impartdispersancy to the V.I. improvers. Examples of suitable unsaturatednitrogen-containing monomers include those containing 4 to 20 carbonatoms such as amino substituted olefins asp-(beta-diethylaminoethyl)styrene; basic nitrogen-containingheterocycles carrying a polymerizable ethylenically unsaturatedsubstituent, e.g. the vinyl pyridines and the vinyl alkyl pyridines suchas 2-vinyl-5-ethyl pyridine, 2-methyl-5-vinyl pyridine,2-vinyl-pyridine, 4-vinylpyridine, 3-vinyl-pyridine,3-methyl-5-vinyl-pyridine, 4-methyl-2-vinyl-pyridine,4-ethyl-2-vinyl-pyridine and 2-butyl-1-5-vinyl-pyridine and the like.

N-vinyl lactams are also suitable, e.g. N-vinyl pyrrolidones or N-vinylpiperidones.

The vinyl pyrrolidones are preferred and are exemplified by N-vinylpyrrolidone, N- (1-methylvinyl) pyrrolidone, N-vinyl-5-methylpyrrolidone, N-vinyl-3, 3-dimethylpyrrolidone, N-vinyl-5-ethylpyrrolidone, etc.

Dihydrocarbyl dithiophosphate metal salts are frequently used asanti-wear agents and also provide antioxidant activity. The zinc saltsare most commonly used in lubricating oil in amounts of 0.1 to 10,preferably 0.2 to 2wt. %, based upon the total weight of the lubricatingoil composition. They may be prepared in accordance with knowntechniques by first forming a dithiophosphoric acid, usually by reactionof an alcohol or a phenol with P₂ S₅ and then neutralizing thedithiophosphoric acid with a suitable zinc compound.

Mixtures of alcohols may be used including mixtures of primary andsecondary alcohols, secondary generally for imparting improved anti-wearproperties, with primary giving improved thermal stability properties.Mixtures of the two are particularly useful. In general, any basic orneutral zinc compound could be used but the oxides, hydroxides andcarbonates are most generally employed. Commercial additives frequentlycontain an excess of zinc due to use of an excess of the basic zinccompound in the neutralization reaction.

The zinc dihydrocarbyl dithiophosphates useful in the present inventionare oil soluble salts of dihydrocarbyl esters of dithiophosphoric acidsand may be represented by the following formula: ##STR24## wherein R andR' may be the same or different hydrocarbyl radicals containing from 1to 18, preferably 2 to 12 carbon atoms and including radicals such asalkyl, alkenyl, aryl, aralkyl, alkaryl and cycloaliphatic radicals.Particularly preferred as R and R' groups are alkyl groups of 2 to 8carbon atoms. Thus, the radicals may, for example, be ethyl, n-propyl,i-propyl, n-butyl, i-butyl, sec-butyl, amyl, n-hexyl, i-hexyl, n-octyl,decyl, dodecyl, octadecyl, 2-ethylhexy 1, phenyl, butylphenyl,cyclohexyl, methylcyclopentyl, propenyl, butenyl etc. In order to obtainoil solubility, the total number of carbon atoms (i.e., R and R' informula XVI) in the dithiophosphoric acid will generally be about 5 orgreater.

The antioxidants useful in this invention include oil soluble coppercompounds. The copper may be blended into the oil as any suitable oilsoluble copper compound. By oil soluble we mean the compound is oilsoluble under normal blending conditions in the oil or additive package.The copper compound may be in the cuprous or cupric form. The copper maybe in the form of the copper dihydrocarbyl thio- or dithio-phosphateswherein copper may be substituted for zinc in the compounds andreactions described above although one mole of cuprous or cupric oxidemay be reacted with one or two moles of the dithiophosphoric acid,respectively. Alternatively the copper may be added as the copper saltof a synthetic or natural carboxylic acid. Examples include C₁₀ to C₁₈fatty acids such as stearic or palmitic, but unsaturated acids such asoleic or branched carboxylic acids such as napthenic acids of molecularweight from 200 to 500 or synthetic carboxylic acids are preferredbecause of the improved handling and solubility properties of theresulting copper carboxylates. Also useful are oil soluble copperdithiocarbamates of the general formula (RR'NCSS)_(n) Cu, where n is 1or 2 and R and R' are the same or different hydrocarbyl radicalscontaining from 1 to 18 and preferably 2 to 12 carbon atoms andincluding radicals such as alkyl, alkenyl, aryl, aralkyl, alkaryl andcycloaliphatic radicals. Particularly preferred as R and R' groups arealkyl groups of 2 to 8 carbon atoms. Thus, the radicals may, forexample, be ethyl, n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl,amyl, n-hexyl, i-hexyl, n-heptyl, n-octyl, decyl, dodecyl, octadecyl,2-ethylhexyl, phenyl, butylphenyl, cyclohexyl, methylcyclopentyl,propenyl, butenyl, etc. In order to obtain oil solubility, the totalnumber of carbon atoms (i.e, R and R') will generally be about 5 orgreater. Copper sulphonates, phenates, and acetylacetonates may also beused.

Exemplary of useful copper compounds are copper (Cu^(I) and/or Cu^(II))salts of alkenyl succinic acids or anhydrides. The salts themselves maybe basic, neutral or acidic. They may be formed by reacting (a) any ofthe materials discussed above in the Ashless Dispersant section, whichhave at least one free carboxylic acid (or anhydride) group with (b) areactive metal compound. Suitable acid (or anhydride) reactive metalcompounds include those such as cupric or cuprous hydroxides, oxides,acetates, borates, and carbonates or basic copper carbonate.

Examples of the metal salts of this invention are Cu salts ofpolyisobutenyl succinic anhydride (hereinafter referred to as Cu-PIBSA),and Cu salts of polyisobutenyl succinic acid. Preferably, the selectedmetal employed is its divalent form e g., CU⁺². The preferred substratesare polyalkenyl succinic acids in which the alkenyl group has amolecular weight greater than about 700. The alkenyl group desirably hasa M_(n) from about 900 to 1400, and up to 2500, with a M_(n) of about950 being most preferred. Especially preferred, of those listed above inthe section on Dispersants, is polyisobutylene succinic acid (PIBSA).These materials may desirably be dissolved in a solvent, such as amineral oil, and heated in the presence of a water solution (or slurry)of the metal bearing material. Heating may take place between 70° andabout 200° C. Temperatures of 110° to 140° C. are entirely adequate. Itmay be necessary, depending upon the salt produced, not to allow thereaction to remain at a temperature above about 140° C. for an extendedperiod of time, e.g., longer than 5 hours, or decomposition of the saltmay occur.

The copper antioxidants (e.g., Cu-PIBSA, Cu-oleate, or mixtures thereof)will be generally employed in an amount of from about 50-500 ppm byweight of the metal, in the final lubricating or fuel composition.

The copper antioxidants used in this invention are inexpensive and areeffective at low concentrations and therefore do not add substantiallyto the cost of the product. The results obtained are frequently betterthan those obtained with previously used antioxidants, which areexpensive and used in higher concentrations. In the amounts employed,the copper compounds do not interfere with the performance of othercomponents of the lubricating composition, in many instances, completelysatisfactory results are obtained when the copper compound is the soleantioxidant in addition to the ZDDP. The copper compounds can beutilized to replace part or all of the need for supplementaryantioxidants. Thus, for particularly severe conditions it may bedesirable to include a supplementary, conventional antioxidant. However,the amounts of supplementary antioxidant required are small, far lessthan the amount required in the absence of the copper compound.

While any effective amount of the copper antioxidant can be incorporatedinto the lubricating oil composition, it is contemplated that sucheffective amounts be sufficient to provide said lube oil compositionwith an amount of the copper antioxidant of from about 5 to 500 (morepreferably 10 to 200, still more preferably 10 to 180, and mostpreferably 20 to 130 (e.g., 90 to 120)) part per million of added copperbased on the weight of the lubricating oil composition. Of course, thepreferred amount may depend amongst other factors on the quality of thebasestock lubricating oil.

Corrosion inhibitors, also known as anti-corrosive agents, reduce thedegradation of the metallic parts contacted by the lubricating oilcomposition. Illustrative of corrosion inhibitors are phosphosulfurizedhydrocarbons and the products obtained by reaction of aphosphosulfurized hydrocarbon with an alkaline earth metal oxide orhydroxide, preferably in the presence of an alkylated phenol or of analkylphenol thioester, and also preferably in the presence of carbondioxide. phosphosulfurized hydrocarbons are prepared by reacting asuitable hydrocarbon such as a terpene, a heavy petroleum fraction of aC₂ to C₆ olefin polymer such as polyisobutylene, with from 5 to 30weight percent of a sulfide of phosphorus for 1/2 to 15 hours, at atemperature in the range of 65° to 315° C. Neutralization of thephosphosulfurized hydrocarbon may be effected in the manner taught inU.S. Pat. No. 1,969,324.

Oxidation inhibitors reduce the tendency of mineral oils to deterioratein service which deterioration can be evidenced by the products ofoxidation such as sludge and varnish-like deposits on the metal surfacesand by viscosity growth. Such oxidation inhibitors include alkalineearth metal salts of alkylphenolthioesters having preferably C₅ to C₁₂alkyl side chains, calcium nonylphenol sulfide, barium t-octylphenylsulfide, dioctylphenylamine, phenylalphanaphthylamine, phosphosulfurizedor sulfurized hydrocarbons, etc.

Friction modifiers serve to impart the proper friction characteristicsto lubricating oil compositions such as automatic transmission fluids.

Representative examples of suitable friction modifiers are found in U.S.Pat. No. 3,933,659 which discloses fatty acid esters and amides; U.S.Pat. No. 4,176,074 which describes molybdenum complexes ofpolyisobutenyl succinic anhydride-amino alkanols; U.S. Pat. No. 4,105,571 which discloses glycerol esters of dimerized fatty acids; U.S. Pat.No. 3,779,928 which discloses alkane phosphonic acid salts; U.S. Pat.No. 3,778,375 which discloses reaction products of a phosphonate with anoleamide; U.S. Pat. No. 3,852,205 which discloses S-carboxy-alkylenehydrocarbyl succinimide, S-carboxyalkylene hydrocarbyl succinamic acidand mixtures thereof; U.S. Pat. No. 3,879,306 which disclosesN-(hydroxyalkyl) alkenyl-succinamic acids or succinimides; U.S. Pat. No.3,932,290 which discloses reaction products of di-(lower alkyl)phosphites and epoxides; and U.S. Pat. No. 4,028,258 which discloses thealkylene oxide adduct of phosphosulfurized N-(hydroxyalkyl) alkenylsuccinimides. The disclosures of the above references are hereinincorporated by reference. The most preferred friction modifiers areglycerol mono and dioleates, and succinate esters, or metal saltsthereof, of hydrocarbyl substituted succinic acids or anhydrides andthiobis alkanols such as described in U.S. Pat. No. 4,344,853.

Pour point depressants lower the temperature at which the fluid willflow or can be poured. Such depressants are well known. Typical of thoseadditives which usefully optimize the low temperature fluidity of thefluid are C₈ -C₁₈ dialkylfumarate vinyl acetate copolymers,polymethacrylates, and wax naphthalene,

Foam control can be provided by an antifoamant of the polysiloxane type,e.g. silicone oil and polydimethyl siloxane.

Organic, oil-soluble compounds useful as rust inhibitors in thisinvention comprise nonionic surfactants such as polyoxyalkylene polyolsand esters thereof, and anionic surfactants such as salts of alkylsulfonic acids. Such anti-rust compounds are known and can be made byconventional means. Nonionic surfactants, useful as anti-rust additivesin the oleaginous compositions of this invention, usually owe theirsurfactant properties to a number of weak stabilizing groups such asether linkages. Nonionic anti-rust agents containing ether linkages canbe made by alkoxylating organic substrates containing active hydrogenswith an excess of the lower alkylene oxides (such as ethylene andpropylene oxides) until the desired number of alkoxy groups have beenplaced in the molecule.

The preferred rust inhibitors are polyoxyalkylene polyols andderivatives thereof. This class of materials are commercially availablefrom various sources: Pluronic Polyols from Wyandotte ChemicalsCorporation; Polyglycol 112-2, a liquid triol derived from ethyleneoxide and propylene oxide available from Dow Chemical Co.; and Tergitol,dodecylphenyl or monophenyl polyethylene glycol ethers, and Ucon,polyalkylene glycols and derivatives, both available from Union CarbideCorp. These are but a few of the commercial products suitable as rustinhibitors in the improved composition of the present invention.

In addition to the polyols per se, the esters thereof obtained byreacting the polyols with various carboxylic acids are also suitable.Acids useful in preparing these esters are lauric acid, stearic acid,succinic acid, and alkyl- or alkenyl-substituted succinic acids whereinthe alkyl-or alkenyl group contains up to about twenty carbon atoms.

The preferred polyols are prepared as block polymers. Thus, ahydroxy-substituted compound, R--(OH)n (wherein n is 1 to 6, and R isthe residue of a mono- or polyhydric alcohol, phenol, naphthol, etc.) isreacted with propylene oxide to form a hydrophobic base. This base isthen reacted with ethylene oxide to provide a hydrophylic portionresulting in a molecule having both hydrophobic and hydrophylicportions. The relative sizes of these portions can be adjusted byregulating the ratio of reactants, time of reaction, etc., as is obviousto those skilled in the art. Thus it is within the skill of the art toprepare polyols whose molecules are characterized by hydrophobic andhydrophylic moieties which are present in a ratio rendering rustinhibitors suitable for use in any lubricant composition regardless ofdifferences in the base oils and the presence of other additives.

If more oil-solubility is needed in a given lubricating composition, thehydrophobic portion can be increased and/or the hydrophylic portiondecreased. If greater oil-in-water emulsion breaking ability isrequired, the hydrophylic and/or hydrophobic portions can be adjusted toaccomplish this.

Compounds illustrative of R--(OH)n include alkylene polyols such as thealkylene glycols, alkylene triols, alkylene tetrols, etc., such asethylene glycol, propylene glycol, glycerol, pentaerythritol, sorbitol,mannitol, and the like. Aromatic hydroxy compounds such as alkylatedmono- and polyhydric phenols and naphthols can also be used, e.g.,heptylphenol, dodecylphenol, etc.

Other suitable demulsifiers include the esters disclosed in U.S. Pat.Nos. 3,098,827 and 2,674,619.

The liquid polyols available from Wyandotte Chemical Co. under the namePluronic Polyols and other similar polyols are particularly well suitedas rust inhibitors. These Pluronic Polyols correspond to the formula:##STR25## wherein x, y, and z are integers greater than 1 such that the--CH₂ CH₂ O-- groups comprise from about 10% to about 40% by weight ofthe total molecular weight of the glycol, the average molecule weight ofsaid glycol being from about 1000 to about 5000. These products areprepared by first condensing propylene oxide with propylene glycol toproduce the hydrophobic base ##STR26## This condensation product is thentreated with ethylene oxide to add hydrophylic portions to both ends ofthe molecule. For best results, the ethylene oxide units should comprisefrom about 10 to about 40% by weight of the molecule. Those productswherein the molecular weight of the polyol is from about 2500 to 4500and the ethylene oxide units comprise from about 10% to about 15% byweight of the molecule are particularly suitable. The polyols having amolecular weight of about 4000 with about 10% attributable to (CH₂ CH₂O) units are particularly good. Also useful are alkoxylated fattyamines, amides, alcohols and the like, including such alkoxylated fattyacid derivatives treated with C₉ to C₁₆ alkyl-substituted phenols (suchas the mono- and di-heptyl, octyl, nonyl, decyl, undecyl, dodecyl andtridecyl phenols), as described in U.S. Pat. No. 3,849,501, which isalso hereby incorporated by reference in its entirety.

These compositions of our invention may also contain other additivessuch as those previously described, and other metal containingadditives, for example, those containing barium and sodium.

The lubricating composition of the present invention may also includecopper lead bearing corrosion inhibitors. Typically such compounds arethe thiadiazole polysulphides containing from 5 to 50 carbon atoms,their derivatives and polymers thereof. Preferred materials are thederivatives of 1,3,4-thiadiazoles such as those described in U.S. Pat.Nos. 2,719,125; 2,719,126; and 3,087,93 2; especially preferred is thecompound 2,5 bis (t-octadithio)-1,3,4-thiadiazole commercially availableas Amoco 150. Other similar materials also suitable are described inU.S. Pat. Nos. 3,821,236; 3,904,537; 4,097,387; 4,107,059; 4,136,043;4,188,299; and 4,193,882.

Other suitable additives are the thio and polythio sulphenamides ofthiadiazoles such as those described in U.K. Patent Specification1,560,830. When these compounds are included in the lubricatingcomposition, we prefer that they be present in an amount from 0.01 to10, preferably 0.1 to 5.0 weight percent based on the weight of thecomposition.

Some of these numerous additives can provide a multiplicity of effects,e.g. a dispersant-oxidation inhibitor. This approach is well known andneed not be further elaborated herein.

Compositions when containing these conventional additives are typicallyblended into the base oil in amounts effective to provide their normalattendant function. Representative effective amounts of such additives(as the respective active ingredients) in the fully formulated oil areillustrated as follows:

    ______________________________________                                                         Wt. % A.I.  Wt. % A.I.                                       Compositions     (Preferred) (Broad)                                          ______________________________________                                        Viscosity Modifier                                                                             0.01-4      0.01-12                                          Detergents       0.01-3      0.01-20                                          Corrosion Inhibitor                                                                            0.01-1.5    .01-5                                            Oxidation Inhibitor                                                                            0.01-1.5    .01-5                                            Dispersant       0.1-8       .1-20                                            Pour Point Depressant                                                                          0.01-1.5    .01-5                                            Anti-Foaming Agents                                                                            0.001-0.15  .001-3                                           Anti-Wear Agents 0.001-1.5   .001-5                                           Friction Modifiers                                                                             0.01-1.5    .01-5                                            Mineral Oil Base Balance     Balance                                          ______________________________________                                    

When other additives are employed, it may be desirable, although notnecessary, to prepare additive concentrates comprising concentratedsolutions or dispersions of the novel dispersants of this invention (inconcentrate amounts hereinabove described), together with one or more ofsaid other additives (said concentrate when constituting an additivemixture being referred to herein as an additive-package) whereby severaladditives can be added simultaneously to the base oil to form thelubricating oil composition. Dissolution of the additive concentrateinto the lubricating oil may be facilitated by solvents and by mixingaccompanied with mild heating, but this is not essential. Theconcentrate or additive-package will typically be formulated to containthe additives in proper amounts to provide the desired concentration inthe final formulation when the additive-package is combined with apredetermined amount of base lubricant. Thus, the dispersants of thepresent invention can be added to small amounts of base oil or othercompatible solvents along with other desirable additives to formadditive-packages containing active ingredients in collective amounts oftypically from about 2.5 to about 90%, and preferably from about 15 toabout 75%, and most preferably from about 25 to about 60% by weightadditives in the appropriate proportions with the remainder being baseoil.

The final formulations may employ typically about 10wt. % of theadditive-package with the remainder being base oil.

All of said weight percents expressed herein (unless otherwiseindicated) are based on active ingredient (A.I.) content of theadditive, and/or upon the total weight of any additive-package, orformulation which will be the sum of the A.I. weight of each additiveplus the weight of total oil or diluent.

This invention will be further understood by reference to the followingexamples, wherein all parts are parts by weight, unless otherwise notedand which include preferred embodiments of the invention.

EXAMPLE 1--PREPARATION OF ETHYLENE PROPYLENE COPOLYMER

A 1 liter Zipperclave reactor (Autoclave Engineers ) equipped with awater jacket for temperature control, with a septum inlet for syringeinjection of catalyst, and with a supply of purified nitrogen, liquidpropylene, and ethylene was used used in these polymerizations. Thereactor was cleaned with hot toluene and then was purged well with drynitrogen at 100° C. The reactor was cooled to 25 ° C. and 10.0 cc of a4.0wt. % toluene solution of methylalumoxane was injected along with 100cc of distilled toluene at 0 psig under nitrogen. Liquid propylenemonomer (2 00 cc ) was added from a calibrated burette at 25° C. Thereactor contents were stirred and heated to 115° C. at which point thereactor pressure was 375 psig. 1.00 cc of a toluene solution ofbis(n-butylcyclopentadienyl )zirconium dichloride (1.00 mg) was injectedand ethylene at a pressure of 405 psig was immediately supplied.Ethylene was fed on pressure demand in order to keep the system pressureat 405 psig. The rate of ethylene flow was recorded continuously duringthe course of the polymerization. The reaction was continued for 15minutes after which the reaction was stopped by rapidly depressuring andcooling the reactor to 25° C. The polymer product was collected and thetoluene solvent was evaporated in an air stream. The polymer weight wasdetermined to be 103.1 gms, and the polymer was analyzed bysize-exclusion chromatography and found to have a number averagemolecular weight of 1100, a weight average molecular weight of 5400 anda polydispersity of 4.9. The polymer product was found to contain 2.5ppm Zr and 1.75 ppm Cl.

EXAMPLE 2--ALKYLATION OF PHENOL

About 50 g. of the ethylene-propylene copolymer produced in Example 1was dissolved in 100 ml of chlorobenzene and added to a solutioncontaining 10.45 g. of phenol in 300 ml of chlorobenzene. While stirringat room temperature under a nitrogen blanket, 0.5 g. of BF₃ gas wasbubbled into the charged solution, and the reaction mixture was stirredwhile the temperature was increased to 50° C. for about 1 hour. Thereaction mixture was then neutralized with gaseous ammonia until aneutral pH was obtained. The solution was filtered and the filtrate washeated to 150° C. to distill of the solvent and excess phenol.Analytical results showed 91.4 % conversion to the desiredethylene-propylene copolymer substituted phenol. No trace of double bondpeak at 890 cm⁻¹ was found in the infra-red analysis of the alkylatedphenol product so produced.

EXAMPLE 3--MANNICH BASE CONDENSATION

25 Grams of the alkylated phenol prepared as in Example 2 is dissolvedin 25 g. of S150N lubricating oil. To the solution is added 0.61 g. of1,6-hexanediamine and 0.35 g. of formaldehyde at 30° C. under N₂. Themixture was heated to 115° C. and kept at that temperature for 1 hour ina four necked round bottomed 500 mol flask. Then, the reaction mixture'stemperature was raised to 130° C. while the reaction vessel was sweptwith dry N₂ gas for 45 minutes. The stripped reaction mixture was thencooled to room temperature, diluted with 100 ml. of heptane, andfiltered. The filtrate was then stripped at 130° C. with dry N₂ gas toremove heptane. The resulting Mannich base condensation product wasevaluated to determine its dispersancy properties and its viscometricproperties.

The product mixture of Example 3 was determined to have a kinematicviscosity of 6.4 cSt (at 100° C., ASTM Method D445) and a CCS viscosityof 23.39 (at -20° C., ASTM Method D2602), thereby providing a VR valueof about 3.6, as compared to the S150N oil itself which has a KV of 5.2cSt and a CCS viscosity of 19.2 cSt, or a VR_(r) of 3.7.

The dispersancy of the thus-prepared product is tested for sludgeinhibition (via the SIB test) and varnish inhibition (via the VIB test).The SIB test has been found, after a large number of evaluations, to bean excellent test for assessing the dispersing power of lubricating oildispersant additives.

The medium chosen for the SIB test is a used crankcase minerallubricating oil composition having an original viscosity of about 325SUS at 38° C. that had been used in a taxicab that is driven generallyfor short trips only, thereby causing a buildup of a high concentrationof sludge precursors. The oil that is used contains only a refined basemineral lubricating oil, a viscosity index improver, a pour pointdepressant and zinc dialkyldithiophosphate anti-wear additive. The oilcontains no sludge dispersant. A quantity of such used oil is acquiredby draining and refilling the taxicab crankcase at 1000-2000 mileintervals.

The SIB test is conducted in the following manner: the aforesaid usedcrankcase oil, which is milky brown in color, is freed of sludge bycentrifuging for one hour at about 39,000 gravities (gs.). The resultingclear bright red supernatant oil is then decanted from the insolublesludge particles thereby separated out. However, the supernatant oilstill contains oil-soluble sludge precursors which on heating under theconditions employed by this test will tend to form additionaloil-insoluble deposits of sludge. The sludge inhibiting properties ofthe additives being tested are determined by adding to portions of thesupernatant used oil, a small amount, such as 0.5, 1 or 2 weightpercent, of the particular additive being tested. Ten grams of eachblend being tested are placed in a stainless steel centrifuge tube andare heated at 135° C. for 16 hours in the presence of air. Following theheating, the tube containing the oil being tested is cooled and thencentrifuged for about 30 minutes at room temperature at about 39,000 gs.Any deposits of new sludge that form in this step are separated from theoil by decanting the supernatant oil and then carefully washing thesludge deposits with 25 ml of heptane to remove all remaining oil fromthe sludge and further centrifuging. The weight of the new solid sludgethat has been formed in the test, in milligrams, is determined by dryingthe residue and weighing it. The results are reported as amount ofprecipitated sludge in comparison with the precipitated sludge of ablank not containing any additional additive, which blank is normalizedto a rating of 10. The less new sludge precipitated in the presence ofthe additive, the lower the SIB value and the more effective is theadditive as a sludge dispersant. In other words, if the additive giveshalf as much precipitated sludge as the blank, then it would be rated5.0 since the blank will be normalized to 10.

The VIB test is used to determine varnish inhibition. Here, the testsample consists of 10 grams of lubricating oil containing a small amountof the additive being tested. The test oil to which the additive isadmixed is of the same type as used in the above-described SIB test. Theten gram sample is heat soaked overnight at about 140° C. and thereaftercentrifuged to remove the sludge. The supernatant fluid of the sample issubjected to heat cycling from about 150° C. to room temperature over aperiod of 3.5 hours at a frequency of about 2 cycles per minute. Duringthe heating phase, gas which was a mixture of about 0.7 volume percentSO₂, 1.4 volume percent NO and balance air is bubbled through the testsample. During the cooling phase, water vapor is bubbled through thetest sample. At the end of the test period, which testing cycle can berepeated as necessary to determine the inhibiting effect of anyadditive, the wall surfaces of the test flask in which the sample iscontained are visually evaluated as to the varnish inhibition. Theamount of varnish imposed on the walls is rated to values of from 1 to11 with the higher number being the greater amount of varnish, incomparison with a blank with no additive that was rated 11.

10.00 grams of SIB test oil are mixed with 0.05 grams of the product ofExample 2 and tested in the aforedescribed SIB and VIB tests.

The dispersant material of Example 3 provided a SIB rating of 6.0, and aVIB rating of 2.5, indicating the presence of dispersant properties.

The principles, preferred embodiments, and modes of operation of thepresent invention have been described in the foregoing specification.The invention which is intended to be protected herein, however, is notto be construed as limited to the particular forms disclosed, sincethese are to be regarded as illustrative rather than restrictive.Variations and changes may be made by those skilled in the art withoutdeparting from the spirit of the invention.

What is claimed is:
 1. A borated lubricating oil dispersant additiveuseful in oleaginous compositions which comprises a product obtained by.treating with a boron compound a condensation product obtained by thereaction of:(a) at least one alkyl-substituted hydroxyaromatic compoundformed by the alkylation of at least one hydroxy aromatic compound withat least one terminally unsaturated ethylene alpha-olefin polymer of 300to 20,000 number average molecular weight, at least 30% of saidpolymer's chains contain terminal ethenylidene unsaturation; (b) atleast one aldehyde reaction; and (c) at least one nucleophilic reactant.2. The borated dispersant additive of claim 1 wherein said polymercomprises an ethylene-propylene copolymer.
 3. The borated dispersantadditive of claim 1 wherein said copolymer has a number averagemolecular weight of from about 700 to about 15,000.
 4. The borateddispersant additive of claim 3 wherein said number average molecularweight is between about 1,500 and 5,000.
 5. The borated dispersantadditive of claim 1 wherein said polymer has a molar ethylene content ofbetween about 20 and about 80 percent.
 6. The borated dispersantadditive of claim 2 wherein said polymer has a molar ethylene content ofbetween about 45 and about 65 percent.
 7. The borated dispersantadditive of claim 1 wherein said alpha-olefin comprises butene-1.
 8. Theborated dispersant additive of claim 2 wherein said number averagemolecular weight is between about 1,500 and 5,000.
 9. The borateddispersant additive according to claim 1 wherein the nucleophilicreagent comprises an amine containing from 2 to 60 carbon atoms and from1 to 12 nitrogen atoms per molecule.
 10. The borated dispersant additiveaccording to claim 9 wherein said amine comprises apolyalkylenepolyamine wherein said alkaline group contains 2 to 60carbons and said polyalkylenepolyamine contains from 2 to about 9nitrogen atoms per molecule.
 11. The borated dispersant additiveaccording to claim 10 wherein said amine comprisespolyethylenepolyamine.
 12. The borated dispersant additive according toclaim 1 wherein said dispersant additive contains from about 0.05 to 2.0weight percent boron.
 13. The borated dispersant additive of claim 12wherein said polymer comprises a member selected from the groupconsisting of ethylene-butene-1 copolymer and an ethylene-propylenecopolymer.
 14. A lubricating oil composition containing from about 0.1to 20 weight percent of the dispersant adduct of claim
 12. 15. A processfor producing a low sediment borated lubricating oil dispersant materialwhich comprises contacting (A) at least one alkyl-substitutedhydroxyaromatic compound formed by the alkylation of at least onehydroxy aromatic compound with at least one ethylene alpha-olefinpolymer of 300 to 20,000 number average molecular weight, wherein atleast 30% of said polymer's chains contain terminal ethenylideneunsaturation, (B) at least one aldehyde reactant; and (C) at least onenucleophilic reactant, under condensation conditions to form acondensation product; and treating the condensation product with a boroncompound to provide the borated dispersant material.
 16. The processaccording to claim 15, wherein said borated dispersant material containsfrom about 0.05 to 2.0 weight percent boron.
 17. The process of claim 16wherein said polymer comprises an ethylene-propylene copolymer.
 18. Theprocess of claim 16 wherein said alpha-olefin comprises butene-1. 19.The process of claim 18 or claim 17 wherein said copolymer has a numberaverage molecular weight of from about 700 to about 15,000.